diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index be981cc7..73f11a59 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -379,3 +379,9 @@ jobs:
       - uses: actions/checkout@v3
       - run: sudo apt install -y shellcheck
       - run: git grep -l '^#\( *shellcheck \|!\(/bin/\|/usr/bin/env \)\(sh\|bash\|dash\|ksh\)\)' | xargs shellcheck
+
+  spec_links:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - run: python test_spec_links.py
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 58ff2b6a..2fb2e353 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -83,7 +83,7 @@
 - SPARQL: If written explicitly in the SPARQL query, the regular expressions are now compiled once and not for each row.
 - SPARQL: Property path evaluation with both start and end variables bound has been optimized.
 - SPARQL: Casts to `xsd:decimal` from `xsd:float` and `xsd:double` now properly fails on overflow instead of overflowing the internal 128-bits representation.
-  This follows [XPath casting rules](https://www.w3.org/TR/xpath-functions/#casting-to-decimal).
+  This follows [XPath casting rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-decimal).
 - Rust: The minimal supported Rust version is set at 1.60 and enforced using the CI.
 - Python: Local builds will now target the specific Python version instead of [abi3](https://docs.python.org/3/c-api/stable.html).
   abi3 wheels are still released on Pypi alongside new Python-version specific builds for Linux+GNU.
@@ -254,7 +254,7 @@
 ## [0.3.0-beta.1] - 2022-01-29
 
 ### Added
-- [RDF-star](https://w3c.github.io/rdf-star/cg-spec) support. `Triple` is now a possible `Term`. Serialization formats and SPARQL support have been updated to match the [latest version of the specification draft](https://w3c.github.io/rdf-star/cg-spec/2021-07-01.html).
+- [RDF-star](https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html) support. `Triple` is now a possible `Term`. Serialization formats and SPARQL support have been updated to match the [latest version of the specification draft](https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html).
 - Fast data bulk load with the `Store` `bulk_load_dataset` and `bulk_load_graph` methods and a special command line option of the server.
 - It is now possible to quickly backup the database using the `backup` method.
 - Rust: `*Syntax::from_extension` to easy guess a graph/dataset/sparql result format from a file extension.
@@ -264,7 +264,7 @@
 - `Store` operations are now transactional using the "repeatable read" isolation level:
   the store only exposes changes that have been "committed" (i.e. no partial writes) and the exposed state does not change for the complete duration of a read operation (e.g. a SPARQL query) or a read/write operation (e.g. a SPARQL update).
   the `Store` `transaction` method now allows to do read/write transactions.
--`RDF-star <https://w3c.github.io/rdf-star/cg-spec>`_ is now supported (including serialization formats and SPARQL-star). :py:class:`.Triple` can now be used in :py:attr:`.Triple.object`, :py:attr:`.Triple.object`, :py:attr:`.Quad.subject` and :py:attr:`.Quad.object`.
+-`RDF-star <https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html>`_ is now supported (including serialization formats and SPARQL-star). :py:class:`.Triple` can now be used in :py:attr:`.Triple.object`, :py:attr:`.Triple.object`, :py:attr:`.Quad.subject` and :py:attr:`.Quad.object`.
 
 ### Changed
 - SPARQL: It is now possible to compare `rdf:langString` literals with the same language tag.
@@ -300,7 +300,7 @@ Many thanks to [Thad Guidry](https://github.com/thadguidry), [James Overton](htt
 ## [0.2.5] - 2021-07-11
 
 ### Added
-- [SPARQL 1.1 Query Results JSON Format](http://www.w3.org/TR/sparql11-results-json/) parser.
+- [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) parser.
 - Python wheels for macOS are now universal2 binaries.
 
 ### Changed
diff --git a/README.md b/README.md
index 06fa4ac1..8f7ed68e 100644
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ Oxigraph implements the following specifications:
 
 - [SPARQL 1.1 Query](https://www.w3.org/TR/sparql11-query/), [SPARQL 1.1 Update](https://www.w3.org/TR/sparql11-update/), and [SPARQL 1.1 Federated Query](https://www.w3.org/TR/sparql11-federated-query/).
 - [Turtle](https://www.w3.org/TR/turtle/), [TriG](https://www.w3.org/TR/trig/), [N-Triples](https://www.w3.org/TR/n-triples/), [N-Quads](https://www.w3.org/TR/n-quads/), and [RDF XML](https://www.w3.org/TR/rdf-syntax-grammar/) RDF serialization formats for both data ingestion and retrieval using the [Rio library](https://github.com/oxigraph/rio).
-- [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
+- [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
 
 A preliminary benchmark [is provided](bench/README.md). There is also [a document describing Oxigraph technical architecture](https://github.com/oxigraph/oxigraph/wiki/Architecture).
 
diff --git a/js/README.md b/js/README.md
index e9e81bfb..576c9739 100644
--- a/js/README.md
+++ b/js/README.md
@@ -242,7 +242,7 @@ store.dump("text/turtle", oxigraph.namedNode("http://example.com/graph"));
 ### From 0.2 to 0.3
 * The `MemoryStore` class is now called `Store` (there is no other kind of stores...).
 * RDF/JS datamodel functions (`namedNode`...) are now available at the root of the `oxigraph` package. You now need to call `oxigraph.namedNode` instead of `store.dataFactory.namedNode`.
-* [RDF-star](https://w3c.github.io/rdf-star/cg-spec) is now implemented. `Quad` is now a valid value for the `Ωuad` `subject` and `object` properties.
+* [RDF-star](https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html) is now implemented. `Quad` is now a valid value for the `Ωuad` `subject` and `object` properties.
 
 ## How to contribute
 
diff --git a/lib/README.md b/lib/README.md
index 3b06e005..80d071ff 100644
--- a/lib/README.md
+++ b/lib/README.md
@@ -20,7 +20,7 @@ Oxigraph also provides [a standalone HTTP server](https://crates.io/crates/oxigr
 Oxigraph implements the following specifications:
 * [SPARQL 1.1 Query](https://www.w3.org/TR/sparql11-query/), [SPARQL 1.1 Update](https://www.w3.org/TR/sparql11-update/), and [SPARQL 1.1 Federated Query](https://www.w3.org/TR/sparql11-federated-query/).
 * [Turtle](https://www.w3.org/TR/turtle/), [TriG](https://www.w3.org/TR/trig/), [N-Triples](https://www.w3.org/TR/n-triples/), [N-Quads](https://www.w3.org/TR/n-quads/), and [RDF XML](https://www.w3.org/TR/rdf-syntax-grammar/) RDF serialization formats for both data ingestion and retrieval using the [Rio library](https://github.com/oxigraph/rio).
-* [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
+* [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
 
 A preliminary benchmark [is provided](../bench/README.md). Oxigraph internal design [is described on the wiki](https://github.com/oxigraph/oxigraph/wiki/Architecture).
 
diff --git a/lib/oxrdf/README.md b/lib/oxrdf/README.md
index ee9dc3ec..5993a746 100644
--- a/lib/oxrdf/README.md
+++ b/lib/oxrdf/README.md
@@ -11,7 +11,7 @@ OxRDF is a simple library providing datastructures encoding [RDF 1.1 concepts](h
 
 This crate is intended to be a basic building block of other crates like [Oxigraph](https://crates.io/crates/oxigraph) or [Spargebra](https://crates.io/crates/spargebra).
 
-Support for [RDF-star](https://w3c.github.io/rdf-star/cg-spec/) is available behind the `rdf-star` feature.
+Support for [RDF-star](https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html) is available behind the `rdf-star` feature.
 
 OxRDF is inspired by [RDF/JS](https://rdf.js.org/data-model-spec/) and [Apache Commons RDF](http://commons.apache.org/proper/commons-rdf/).
 
diff --git a/lib/oxrdf/src/dataset.rs b/lib/oxrdf/src/dataset.rs
index 9925f7ca..72a06cc6 100644
--- a/lib/oxrdf/src/dataset.rs
+++ b/lib/oxrdf/src/dataset.rs
@@ -108,7 +108,7 @@ impl Dataset {
         Self::default()
     }
 
-    /// Provides a read-only view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-graph) contained in this dataset.
+    /// Provides a read-only view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-graph) contained in this dataset.
     ///
     /// ```
     /// use oxrdf::*;
@@ -131,7 +131,7 @@ impl Dataset {
         }
     }
 
-    /// Provides a read/write view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-graph) contained in this dataset.
+    /// Provides a read/write view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-graph) contained in this dataset.
     ///
     /// ```
     /// use oxrdf::*;
@@ -908,7 +908,7 @@ impl fmt::Display for Dataset {
     }
 }
 
-/// A read-only view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-graph) contained in a [`Dataset`].
+/// A read-only view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-graph) contained in a [`Dataset`].
 ///
 /// It is built using the [`Dataset::graph`] method.
 ///
@@ -1243,7 +1243,7 @@ impl<'a> fmt::Display for GraphView<'a> {
     }
 }
 
-/// A read/write view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-graph) contained in a [`Dataset`].
+/// A read/write view on an [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-graph) contained in a [`Dataset`].
 ///
 /// It is built using the [`Dataset::graph_mut`] method.
 ///
diff --git a/lib/oxrdf/src/graph.rs b/lib/oxrdf/src/graph.rs
index 804bedf6..195b75a1 100644
--- a/lib/oxrdf/src/graph.rs
+++ b/lib/oxrdf/src/graph.rs
@@ -1,4 +1,4 @@
-//! [In-memory implementation](super::Graph) of  [RDF graphs](https://www.w3.org/TR/rdf11-concepts/#dfn-graph).
+//! [In-memory implementation](super::Graph) of  [RDF graphs](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-graph).
 //!
 //! Usage example:
 //! ```
@@ -26,7 +26,7 @@ use crate::dataset::*;
 use crate::*;
 use std::fmt;
 
-/// An in-memory [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-graph).
+/// An in-memory [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-graph).
 ///
 /// It can accommodate a fairly large number of triples (in the few millions).
 /// Beware: it interns the string and does not do any garbage collection yet:
diff --git a/lib/oxrdf/src/literal.rs b/lib/oxrdf/src/literal.rs
index 438fef9c..6891ba15 100644
--- a/lib/oxrdf/src/literal.rs
+++ b/lib/oxrdf/src/literal.rs
@@ -112,17 +112,17 @@ impl Literal {
 
     /// The literal [datatype](https://www.w3.org/TR/rdf11-concepts/#dfn-datatype-iri).
     ///
-    /// The datatype of [language-tagged string](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string) is always [rdf:langString](http://www.w3.org/1999/02/22-rdf-syntax-ns#langString).
-    /// The datatype of [simple literals](https://www.w3.org/TR/rdf11-concepts/#dfn-simple-literal) is [xsd:string](http://www.w3.org/2001/XMLSchema#string).
+    /// The datatype of [language-tagged string](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string) is always [rdf:langString](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string).
+    /// The datatype of [simple literals](https://www.w3.org/TR/rdf11-concepts/#dfn-simple-literal) is [xsd:string](https://www.w3.org/TR/xmlschema11-2/#string).
     #[inline]
     pub fn datatype(&self) -> NamedNodeRef<'_> {
         self.as_ref().datatype()
     }
 
-    /// Checks if this literal could be seen as an RDF 1.0 [plain literal](https://www.w3.org/TR/rdf-concepts/#dfn-plain-literal).
+    /// Checks if this literal could be seen as an RDF 1.0 [plain literal](https://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-plain-literal).
     ///
     /// It returns true if the literal is a [language-tagged string](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string)
-    /// or has the datatype [xsd:string](http://www.w3.org/2001/XMLSchema#string).
+    /// or has the datatype [xsd:string](https://www.w3.org/TR/xmlschema11-2/#string).
     #[inline]
     pub fn is_plain(&self) -> bool {
         self.as_ref().is_plain()
@@ -510,8 +510,8 @@ impl<'a> LiteralRef<'a> {
 
     /// The literal [datatype](https://www.w3.org/TR/rdf11-concepts/#dfn-datatype-iri).
     ///
-    /// The datatype of [language-tagged string](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string) is always [rdf:langString](http://www.w3.org/1999/02/22-rdf-syntax-ns#langString).
-    /// The datatype of [simple literals](https://www.w3.org/TR/rdf11-concepts/#dfn-simple-literal) is [xsd:string](http://www.w3.org/2001/XMLSchema#string).
+    /// The datatype of [language-tagged string](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string) is always [rdf:langString](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string).
+    /// The datatype of [simple literals](https://www.w3.org/TR/rdf11-concepts/#dfn-simple-literal) is [xsd:string](https://www.w3.org/TR/xmlschema11-2/#string).
     #[inline]
     pub fn datatype(self) -> NamedNodeRef<'a> {
         match self.0 {
@@ -521,10 +521,10 @@ impl<'a> LiteralRef<'a> {
         }
     }
 
-    /// Checks if this literal could be seen as an RDF 1.0 [plain literal](https://www.w3.org/TR/rdf-concepts/#dfn-plain-literal).
+    /// Checks if this literal could be seen as an RDF 1.0 [plain literal](https://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-plain-literal).
     ///
     /// It returns true if the literal is a [language-tagged string](https://www.w3.org/TR/rdf11-concepts/#dfn-language-tagged-string)
-    /// or has the datatype [xsd:string](http://www.w3.org/2001/XMLSchema#string).
+    /// or has the datatype [xsd:string](https://www.w3.org/TR/xmlschema11-2/#string).
     #[inline]
     pub fn is_plain(self) -> bool {
         matches!(
diff --git a/lib/oxsdatatypes/README.md b/lib/oxsdatatypes/README.md
index 213a53f1..1f0b419a 100644
--- a/lib/oxsdatatypes/README.md
+++ b/lib/oxsdatatypes/README.md
@@ -28,7 +28,7 @@ Each datatype provides:
 * `PartialEq`, and `Eq` if possible, implementations following its [equality relation](https://www.w3.org/TR/xmlschema11-2/#equality).
 * `PartialOrd`, and `Ord` if possible, implementations following its [order relation](https://www.w3.org/TR/xmlschema11-2/#order).
 * `From` and `TryFrom` implementations to implement [XPath casting](https://www.w3.org/TR/xpath-functions-31/#casting).
-* Various methods implementing [XPath functions](https://www.w3.org/TR/xpath-functions/).
+* Various methods implementing [XPath functions](https://www.w3.org/TR/xpath-functions-31/).
 * `from_be_bytes` and `to_be_bytes` methods for serialization.
 
 
diff --git a/lib/oxsdatatypes/src/date_time.rs b/lib/oxsdatatypes/src/date_time.rs
index 734ebab5..caaa00b9 100644
--- a/lib/oxsdatatypes/src/date_time.rs
+++ b/lib/oxsdatatypes/src/date_time.rs
@@ -43,7 +43,7 @@ impl DateTime {
         })
     }
 
-    /// [fn:current-dateTime](https://www.w3.org/TR/xpath-functions/#func-current-dateTime)
+    /// [fn:current-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-current-dateTime)
     #[inline]
     pub fn now() -> Result<Self, DateTimeError> {
         Ok(Self {
@@ -58,43 +58,43 @@ impl DateTime {
         }
     }
 
-    /// [fn:year-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-year-from-dateTime)
+    /// [fn:year-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-year-from-dateTime)
     #[inline]
     pub fn year(&self) -> i64 {
         self.timestamp.year()
     }
 
-    /// [fn:month-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-month-from-dateTime)
+    /// [fn:month-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-month-from-dateTime)
     #[inline]
     pub fn month(&self) -> u8 {
         self.timestamp.month()
     }
 
-    /// [fn:day-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-day-from-dateTime)
+    /// [fn:day-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-day-from-dateTime)
     #[inline]
     pub fn day(&self) -> u8 {
         self.timestamp.day()
     }
 
-    /// [fn:hour-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-hour-from-dateTime)
+    /// [fn:hour-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-hours-from-dateTime)
     #[inline]
     pub fn hour(&self) -> u8 {
         self.timestamp.hour()
     }
 
-    /// [fn:minute-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-minute-from-dateTime)
+    /// [fn:minute-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-minutes-from-dateTime)
     #[inline]
     pub fn minute(&self) -> u8 {
         self.timestamp.minute()
     }
 
-    /// [fn:second-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-second-from-dateTime)
+    /// [fn:second-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-seconds-from-dateTime)
     #[inline]
     pub fn second(&self) -> Decimal {
         self.timestamp.second()
     }
 
-    /// [fn:timezone-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-timezone-from-dateTime)
+    /// [fn:timezone-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-timezone-from-dateTime)
     #[inline]
     pub fn timezone(&self) -> Option<DayTimeDuration> {
         Some(self.timezone_offset()?.into())
@@ -123,13 +123,13 @@ impl DateTime {
         self.timestamp.to_be_bytes()
     }
 
-    /// [op:subtract-dateTimes](https://www.w3.org/TR/xpath-functions/#func-subtract-dateTimes)
+    /// [op:subtract-dateTimes](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dateTimes)
     #[inline]
     pub fn checked_sub(&self, rhs: impl Into<Self>) -> Option<DayTimeDuration> {
         self.timestamp.checked_sub(rhs.into().timestamp)
     }
 
-    /// [op:add-yearMonthDuration-to-dateTime](https://www.w3.org/TR/xpath-functions/#func-add-yearMonthDuration-to-dateTime)
+    /// [op:add-yearMonthDuration-to-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-add-yearMonthDuration-to-dateTime)
     #[inline]
     pub fn checked_add_year_month_duration(
         &self,
@@ -138,7 +138,7 @@ impl DateTime {
         self.checked_add_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDuration-to-dateTime)
+    /// [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDuration-to-dateTime)
     #[inline]
     pub fn checked_add_day_time_duration(&self, rhs: impl Into<Duration>) -> Option<Self> {
         let rhs = rhs.into();
@@ -147,7 +147,7 @@ impl DateTime {
         })
     }
 
-    /// [op:add-yearMonthDuration-to-dateTime](https://www.w3.org/TR/xpath-functions/#func-add-yearMonthDuration-to-dateTime) and [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDuration-to-dateTime)
+    /// [op:add-yearMonthDuration-to-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-add-yearMonthDuration-to-dateTime) and [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDuration-to-dateTime)
     #[inline]
     pub fn checked_add_duration(&self, rhs: impl Into<Duration>) -> Option<Self> {
         let rhs = rhs.into();
@@ -161,7 +161,7 @@ impl DateTime {
         }
     }
 
-    /// [op:subtract-yearMonthDuration-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-subtract-yearMonthDuration-from-dateTime)
+    /// [op:subtract-yearMonthDuration-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-subtract-yearMonthDuration-from-dateTime)
     #[inline]
     pub fn checked_sub_year_month_duration(
         &self,
@@ -170,7 +170,7 @@ impl DateTime {
         self.checked_sub_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:subtract-dayTimeDuration-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDuration-from-dateTime)
+    /// [op:subtract-dayTimeDuration-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDuration-from-dateTime)
     #[inline]
     pub fn checked_sub_day_time_duration(&self, rhs: impl Into<DayTimeDuration>) -> Option<Self> {
         let rhs = rhs.into();
@@ -179,7 +179,7 @@ impl DateTime {
         })
     }
 
-    /// [op:subtract-yearMonthDuration-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-subtract-yearMonthDuration-from-dateTime) and [op:subtract-dayTimeDuration-from-dateTime](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDuration-from-dateTime)
+    /// [op:subtract-yearMonthDuration-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-subtract-yearMonthDuration-from-dateTime) and [op:subtract-dayTimeDuration-from-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDuration-from-dateTime)
     #[inline]
     pub fn checked_sub_duration(&self, rhs: impl Into<Duration>) -> Option<Self> {
         let rhs = rhs.into();
@@ -196,7 +196,7 @@ impl DateTime {
         }
     }
 
-    /// [fn:adjust-dateTime-to-timezone](https://www.w3.org/TR/xpath-functions/#func-adjust-dateTime-to-timezone)
+    /// [fn:adjust-dateTime-to-timezone](https://www.w3.org/TR/xpath-functions-31/#func-adjust-dateTime-to-timezone)
     #[inline]
     pub fn adjust(&self, timezone_offset: Option<TimezoneOffset>) -> Option<Self> {
         Some(Self {
@@ -211,7 +211,7 @@ impl DateTime {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<Date> for DateTime {
     type Error = DateTimeError;
 
@@ -306,31 +306,31 @@ impl Time {
         }
     }
 
-    /// [fn:current-time](https://www.w3.org/TR/xpath-functions/#func-current-time)
+    /// [fn:current-time](https://www.w3.org/TR/xpath-functions-31/#func-current-time)
     #[inline]
     pub fn now() -> Result<Self, DateTimeError> {
         DateTime::now()?.try_into()
     }
 
-    /// [fn:hour-from-time](https://www.w3.org/TR/xpath-functions/#func-hour-from-time)
+    /// [fn:hour-from-time](https://www.w3.org/TR/xpath-functions-31/#func-hours-from-time)
     #[inline]
     pub fn hour(&self) -> u8 {
         self.timestamp.hour()
     }
 
-    /// [fn:minute-from-time](https://www.w3.org/TR/xpath-functions/#func-minute-from-time)
+    /// [fn:minute-from-time](https://www.w3.org/TR/xpath-functions-31/#func-minutes-from-time)
     #[inline]
     pub fn minute(&self) -> u8 {
         self.timestamp.minute()
     }
 
-    /// [fn:second-from-time](https://www.w3.org/TR/xpath-functions/#func-second-from-time)
+    /// [fn:second-from-time](https://www.w3.org/TR/xpath-functions-31/#func-seconds-from-time)
     #[inline]
     pub fn second(&self) -> Decimal {
         self.timestamp.second()
     }
 
-    /// [fn:timezone-from-time](https://www.w3.org/TR/xpath-functions/#func-timezone-from-time)
+    /// [fn:timezone-from-time](https://www.w3.org/TR/xpath-functions-31/#func-timezone-from-time)
     #[inline]
     pub fn timezone(&self) -> Option<DayTimeDuration> {
         Some(self.timezone_offset()?.into())
@@ -346,19 +346,19 @@ impl Time {
         self.timestamp.to_be_bytes()
     }
 
-    /// [op:subtract-times](https://www.w3.org/TR/xpath-functions/#func-subtract-times)
+    /// [op:subtract-times](https://www.w3.org/TR/xpath-functions-31/#func-subtract-times)
     #[inline]
     pub fn checked_sub(&self, rhs: impl Into<Self>) -> Option<DayTimeDuration> {
         self.timestamp.checked_sub(rhs.into().timestamp)
     }
 
-    /// [op:add-dayTimeDuration-to-time](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDuration-to-time)
+    /// [op:add-dayTimeDuration-to-time](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDuration-to-time)
     #[inline]
     pub fn checked_add_day_time_duration(&self, rhs: impl Into<DayTimeDuration>) -> Option<Self> {
         self.checked_add_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:add-dayTimeDuration-to-time](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDuration-to-time)
+    /// [op:add-dayTimeDuration-to-time](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDuration-to-time)
     #[inline]
     pub fn checked_add_duration(&self, rhs: impl Into<Duration>) -> Option<Self> {
         DateTime::new(
@@ -376,13 +376,13 @@ impl Time {
         .ok()
     }
 
-    /// [op:subtract-dayTimeDuration-from-time](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDuration-from-time)
+    /// [op:subtract-dayTimeDuration-from-time](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDuration-from-time)
     #[inline]
     pub fn checked_sub_day_time_duration(&self, rhs: impl Into<DayTimeDuration>) -> Option<Self> {
         self.checked_sub_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:subtract-dayTimeDuration-from-time](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDuration-from-time)
+    /// [op:subtract-dayTimeDuration-from-time](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDuration-from-time)
     #[inline]
     pub fn checked_sub_duration(&self, rhs: impl Into<Duration>) -> Option<Self> {
         DateTime::new(
@@ -400,7 +400,7 @@ impl Time {
         .ok()
     }
 
-    // [fn:adjust-time-to-timezone](https://www.w3.org/TR/xpath-functions/#func-adjust-time-to-timezone)
+    // [fn:adjust-time-to-timezone](https://www.w3.org/TR/xpath-functions-31/#func-adjust-time-to-timezone)
     #[inline]
     pub fn adjust(&self, timezone_offset: Option<TimezoneOffset>) -> Option<Self> {
         DateTime::new(
@@ -425,7 +425,7 @@ impl Time {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<DateTime> for Time {
     type Error = DateTimeError;
 
@@ -507,31 +507,31 @@ impl Date {
         }
     }
 
-    /// [fn:current-date](https://www.w3.org/TR/xpath-functions/#func-current-date)
+    /// [fn:current-date](https://www.w3.org/TR/xpath-functions-31/#func-current-date)
     #[inline]
     pub fn now() -> Result<Self, DateTimeError> {
         DateTime::now()?.try_into()
     }
 
-    /// [fn:year-from-date](https://www.w3.org/TR/xpath-functions/#func-year-from-date)
+    /// [fn:year-from-date](https://www.w3.org/TR/xpath-functions-31/#func-year-from-date)
     #[inline]
     pub fn year(&self) -> i64 {
         self.timestamp.year()
     }
 
-    /// [fn:month-from-date](https://www.w3.org/TR/xpath-functions/#func-month-from-date)
+    /// [fn:month-from-date](https://www.w3.org/TR/xpath-functions-31/#func-month-from-date)
     #[inline]
     pub fn month(&self) -> u8 {
         self.timestamp.month()
     }
 
-    /// [fn:day-from-date](https://www.w3.org/TR/xpath-functions/#func-day-from-date)
+    /// [fn:day-from-date](https://www.w3.org/TR/xpath-functions-31/#func-day-from-date)
     #[inline]
     pub fn day(&self) -> u8 {
         self.timestamp.day()
     }
 
-    /// [fn:timezone-from-date](https://www.w3.org/TR/xpath-functions/#func-timezone-from-date)
+    /// [fn:timezone-from-date](https://www.w3.org/TR/xpath-functions-31/#func-timezone-from-date)
     #[inline]
     pub fn timezone(&self) -> Option<DayTimeDuration> {
         Some(self.timezone_offset()?.into())
@@ -547,13 +547,13 @@ impl Date {
         self.timestamp.to_be_bytes()
     }
 
-    /// [op:subtract-dates](https://www.w3.org/TR/xpath-functions/#func-subtract-dates)
+    /// [op:subtract-dates](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dates)
     #[inline]
     pub fn checked_sub(&self, rhs: impl Into<Self>) -> Option<DayTimeDuration> {
         self.timestamp.checked_sub(rhs.into().timestamp)
     }
 
-    /// [op:add-yearMonthDuration-to-date](https://www.w3.org/TR/xpath-functions/#func-add-yearMonthDuration-to-date)
+    /// [op:add-yearMonthDuration-to-date](https://www.w3.org/TR/xpath-functions-31/#func-add-yearMonthDuration-to-date)
     #[inline]
     pub fn checked_add_year_month_duration(
         &self,
@@ -562,13 +562,13 @@ impl Date {
         self.checked_add_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDuration-to-date)
+    /// [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDuration-to-date)
     #[inline]
     pub fn checked_add_day_time_duration(&self, rhs: impl Into<DayTimeDuration>) -> Option<Self> {
         self.checked_add_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:add-yearMonthDuration-to-date](https://www.w3.org/TR/xpath-functions/#func-add-yearMonthDuration-to-date) and [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDuration-to-date)
+    /// [op:add-yearMonthDuration-to-date](https://www.w3.org/TR/xpath-functions-31/#func-add-yearMonthDuration-to-date) and [op:add-dayTimeDuration-to-dateTime](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDuration-to-date)
     #[inline]
     pub fn checked_add_duration(&self, rhs: impl Into<Duration>) -> Option<Self> {
         DateTime::try_from(*self)
@@ -578,7 +578,7 @@ impl Date {
             .ok()
     }
 
-    /// [op:subtract-yearMonthDuration-from-date](https://www.w3.org/TR/xpath-functions/#func-subtract-yearMonthDuration-from-date)
+    /// [op:subtract-yearMonthDuration-from-date](https://www.w3.org/TR/xpath-functions-31/#func-subtract-yearMonthDuration-from-date)
     #[inline]
     pub fn checked_sub_year_month_duration(
         &self,
@@ -587,13 +587,13 @@ impl Date {
         self.checked_sub_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:subtract-dayTimeDuration-from-date](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDuration-from-date)
+    /// [op:subtract-dayTimeDuration-from-date](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDuration-from-date)
     #[inline]
     pub fn checked_sub_day_time_duration(&self, rhs: impl Into<DayTimeDuration>) -> Option<Self> {
         self.checked_sub_duration(Duration::from(rhs.into()))
     }
 
-    /// [op:subtract-yearMonthDuration-from-date](https://www.w3.org/TR/xpath-functions/#func-subtract-yearMonthDuration-from-date) and [op:subtract-dayTimeDuration-from-date](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDuration-from-date)
+    /// [op:subtract-yearMonthDuration-from-date](https://www.w3.org/TR/xpath-functions-31/#func-subtract-yearMonthDuration-from-date) and [op:subtract-dayTimeDuration-from-date](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDuration-from-date)
     #[inline]
     pub fn checked_sub_duration(&self, rhs: impl Into<Duration>) -> Option<Self> {
         DateTime::try_from(*self)
@@ -603,7 +603,7 @@ impl Date {
             .ok()
     }
 
-    // [fn:adjust-date-to-timezone](https://www.w3.org/TR/xpath-functions/#func-adjust-date-to-timezone)
+    // [fn:adjust-date-to-timezone](https://www.w3.org/TR/xpath-functions-31/#func-adjust-date-to-timezone)
     #[inline]
     pub fn adjust(&self, timezone_offset: Option<TimezoneOffset>) -> Option<Self> {
         DateTime::new(
@@ -628,7 +628,7 @@ impl Date {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<DateTime> for Date {
     type Error = DateTimeError;
 
@@ -741,7 +741,7 @@ impl GYearMonth {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<DateTime> for GYearMonth {
     type Error = DateTimeError;
 
@@ -755,7 +755,7 @@ impl TryFrom<DateTime> for GYearMonth {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<Date> for GYearMonth {
     type Error = DateTimeError;
 
@@ -857,7 +857,7 @@ impl GYear {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<DateTime> for GYear {
     type Error = DateTimeError;
 
@@ -867,7 +867,7 @@ impl TryFrom<DateTime> for GYear {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<Date> for GYear {
     type Error = DateTimeError;
 
@@ -984,7 +984,7 @@ impl GMonthDay {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<DateTime> for GMonthDay {
     type Error = DateTimeError;
 
@@ -998,7 +998,7 @@ impl TryFrom<DateTime> for GMonthDay {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<Date> for GMonthDay {
     type Error = DateTimeError;
 
@@ -1096,7 +1096,7 @@ impl GMonth {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<DateTime> for GMonth {
     type Error = DateTimeError;
 
@@ -1106,7 +1106,7 @@ impl TryFrom<DateTime> for GMonth {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<Date> for GMonth {
     type Error = DateTimeError;
 
@@ -1222,7 +1222,7 @@ impl GDay {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<DateTime> for GDay {
     type Error = DateTimeError;
 
@@ -1232,7 +1232,7 @@ impl TryFrom<DateTime> for GDay {
     }
 }
 
-/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions/#casting-to-datetimes).
+/// Conversion according to [XPath cast rules](https://www.w3.org/TR/xpath-functions-31/#casting-to-datetimes).
 impl TryFrom<Date> for GDay {
     type Error = DateTimeError;
 
diff --git a/lib/oxsdatatypes/src/decimal.rs b/lib/oxsdatatypes/src/decimal.rs
index 11065901..19d93fed 100644
--- a/lib/oxsdatatypes/src/decimal.rs
+++ b/lib/oxsdatatypes/src/decimal.rs
@@ -45,7 +45,7 @@ impl Decimal {
         self.value.to_be_bytes()
     }
 
-    /// [op:numeric-add](https://www.w3.org/TR/xpath-functions/#func-numeric-add)
+    /// [op:numeric-add](https://www.w3.org/TR/xpath-functions-31/#func-numeric-add)
     #[inline]
     pub fn checked_add(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -53,7 +53,7 @@ impl Decimal {
         })
     }
 
-    /// [op:numeric-subtract](https://www.w3.org/TR/xpath-functions/#func-numeric-subtract)
+    /// [op:numeric-subtract](https://www.w3.org/TR/xpath-functions-31/#func-numeric-subtract)
     #[inline]
     pub fn checked_sub(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -61,7 +61,7 @@ impl Decimal {
         })
     }
 
-    /// [op:numeric-multiply](https://www.w3.org/TR/xpath-functions/#func-numeric-multiply)
+    /// [op:numeric-multiply](https://www.w3.org/TR/xpath-functions-31/#func-numeric-multiply)
     #[inline]
     pub fn checked_mul(&self, rhs: impl Into<Self>) -> Option<Self> {
         // Idea: we shift right as much as possible to keep as much precision as possible
@@ -93,7 +93,7 @@ impl Decimal {
         })
     }
 
-    /// [op:numeric-divide](https://www.w3.org/TR/xpath-functions/#func-numeric-divide)
+    /// [op:numeric-divide](https://www.w3.org/TR/xpath-functions-31/#func-numeric-divide)
     #[inline]
     pub fn checked_div(&self, rhs: impl Into<Self>) -> Option<Self> {
         // Idea: we shift the dividend left as much as possible to keep as much precision as possible
@@ -126,7 +126,7 @@ impl Decimal {
         })
     }
 
-    /// [op:numeric-mod](https://www.w3.org/TR/xpath-functions/#func-numeric-mod)
+    /// [op:numeric-mod](https://www.w3.org/TR/xpath-functions-31/#func-numeric-mod)
     #[inline]
     pub fn checked_rem(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -141,7 +141,7 @@ impl Decimal {
         })
     }
 
-    /// [op:numeric-unary-minus](https://www.w3.org/TR/xpath-functions/#func-numeric-unary-minus)
+    /// [op:numeric-unary-minus](https://www.w3.org/TR/xpath-functions-31/#func-numeric-unary-minus)
     #[inline]
     pub fn checked_neg(&self) -> Option<Self> {
         Some(Self {
@@ -149,7 +149,7 @@ impl Decimal {
         })
     }
 
-    /// [fn:abs](https://www.w3.org/TR/xpath-functions/#func-abs)
+    /// [fn:abs](https://www.w3.org/TR/xpath-functions-31/#func-abs)
     #[inline]
     pub const fn abs(&self) -> Self {
         Self {
@@ -157,7 +157,7 @@ impl Decimal {
         }
     }
 
-    /// [fn:round](https://www.w3.org/TR/xpath-functions/#func-round)
+    /// [fn:round](https://www.w3.org/TR/xpath-functions-31/#func-round)
     #[inline]
     pub fn round(&self) -> Self {
         let value = self.value / DECIMAL_PART_POW_MINUS_ONE;
@@ -170,7 +170,7 @@ impl Decimal {
         }
     }
 
-    /// [fn:ceiling](https://www.w3.org/TR/xpath-functions/#func-ceiling)
+    /// [fn:ceiling](https://www.w3.org/TR/xpath-functions-31/#func-ceiling)
     #[inline]
     pub fn ceil(&self) -> Self {
         Self {
@@ -182,7 +182,7 @@ impl Decimal {
         }
     }
 
-    /// [fn:floor](https://www.w3.org/TR/xpath-functions/#func-floor)
+    /// [fn:floor](https://www.w3.org/TR/xpath-functions-31/#func-floor)
     #[inline]
     pub fn floor(&self) -> Self {
         Self {
diff --git a/lib/oxsdatatypes/src/double.rs b/lib/oxsdatatypes/src/double.rs
index e9b26ba5..b1465c9e 100644
--- a/lib/oxsdatatypes/src/double.rs
+++ b/lib/oxsdatatypes/src/double.rs
@@ -29,25 +29,25 @@ impl Double {
         self.value.to_be_bytes()
     }
 
-    /// [fn:abs](https://www.w3.org/TR/xpath-functions/#func-abs)
+    /// [fn:abs](https://www.w3.org/TR/xpath-functions-31/#func-abs)
     #[inline]
     pub fn abs(self) -> Self {
         self.value.abs().into()
     }
 
-    /// [fn:ceiling](https://www.w3.org/TR/xpath-functions/#func-ceiling)
+    /// [fn:ceiling](https://www.w3.org/TR/xpath-functions-31/#func-ceiling)
     #[inline]
     pub fn ceil(self) -> Self {
         self.value.ceil().into()
     }
 
-    /// [fn:floor](https://www.w3.org/TR/xpath-functions/#func-floor)
+    /// [fn:floor](https://www.w3.org/TR/xpath-functions-31/#func-floor)
     #[inline]
     pub fn floor(self) -> Self {
         self.value.floor().into()
     }
 
-    /// [fn:round](https://www.w3.org/TR/xpath-functions/#func-round)
+    /// [fn:round](https://www.w3.org/TR/xpath-functions-31/#func-round)
     #[inline]
     pub fn round(self) -> Self {
         self.value.round().into()
diff --git a/lib/oxsdatatypes/src/duration.rs b/lib/oxsdatatypes/src/duration.rs
index a2d6ac47..11ed0c1d 100644
--- a/lib/oxsdatatypes/src/duration.rs
+++ b/lib/oxsdatatypes/src/duration.rs
@@ -33,37 +33,37 @@ impl Duration {
         }
     }
 
-    /// [fn:years-from-duration](https://www.w3.org/TR/xpath-functions/#func-years-from-duration)
+    /// [fn:years-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-years-from-duration)
     #[inline]
     pub fn years(&self) -> i64 {
         self.year_month.years()
     }
 
-    /// [fn:months-from-duration](https://www.w3.org/TR/xpath-functions/#func-months-from-duration)
+    /// [fn:months-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-months-from-duration)
     #[inline]
     pub fn months(&self) -> i64 {
         self.year_month.months()
     }
 
-    /// [fn:days-from-duration](https://www.w3.org/TR/xpath-functions/#func-days-from-duration)
+    /// [fn:days-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-days-from-duration)
     #[inline]
     pub fn days(&self) -> i64 {
         self.day_time.days()
     }
 
-    /// [fn:hours-from-duration](https://www.w3.org/TR/xpath-functions/#func-hours-from-duration)
+    /// [fn:hours-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-hours-from-duration)
     #[inline]
     pub fn hours(&self) -> i64 {
         self.day_time.hours()
     }
 
-    /// [fn:minutes-from-duration](https://www.w3.org/TR/xpath-functions/#func-minutes-from-duration)
+    /// [fn:minutes-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-minutes-from-duration)
     #[inline]
     pub fn minutes(&self) -> i64 {
         self.day_time.minutes()
     }
 
-    /// [fn:seconds-from-duration](https://www.w3.org/TR/xpath-functions/#func-seconds-from-duration)
+    /// [fn:seconds-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-seconds-from-duration)
     #[inline]
     pub fn seconds(&self) -> Decimal {
         self.day_time.seconds()
@@ -87,7 +87,7 @@ impl Duration {
         bytes
     }
 
-    /// [op:add-yearMonthDurations](https://www.w3.org/TR/xpath-functions/#func-add-yearMonthDurations) and [op:add-dayTimeDurations](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDurations)
+    /// [op:add-yearMonthDurations](https://www.w3.org/TR/xpath-functions-31/#func-add-yearMonthDurations) and [op:add-dayTimeDurations](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDurations)
     #[inline]
     pub fn checked_add(&self, rhs: impl Into<Self>) -> Option<Self> {
         let rhs = rhs.into();
@@ -97,7 +97,7 @@ impl Duration {
         })
     }
 
-    /// [op:subtract-yearMonthDurations](https://www.w3.org/TR/xpath-functions/#func-subtract-yearMonthDurations) and [op:subtract-dayTimeDurations](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDurations)
+    /// [op:subtract-yearMonthDurations](https://www.w3.org/TR/xpath-functions-31/#func-subtract-yearMonthDurations) and [op:subtract-dayTimeDurations](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDurations)
     #[inline]
     pub fn checked_sub(&self, rhs: impl Into<Self>) -> Option<Self> {
         let rhs = rhs.into();
@@ -269,13 +269,13 @@ impl YearMonthDuration {
         }
     }
 
-    /// [fn:years-from-duration](https://www.w3.org/TR/xpath-functions/#func-years-from-duration)
+    /// [fn:years-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-years-from-duration)
     #[inline]
     pub fn years(self) -> i64 {
         self.months / 12
     }
 
-    /// [fn:months-from-duration](https://www.w3.org/TR/xpath-functions/#func-months-from-duration)
+    /// [fn:months-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-months-from-duration)
     #[inline]
     pub fn months(self) -> i64 {
         self.months % 12
@@ -291,7 +291,7 @@ impl YearMonthDuration {
         self.months.to_be_bytes()
     }
 
-    /// [op:add-yearMonthDurations](https://www.w3.org/TR/xpath-functions/#func-add-yearMonthDurations)
+    /// [op:add-yearMonthDurations](https://www.w3.org/TR/xpath-functions-31/#func-add-yearMonthDurations)
     #[inline]
     pub fn checked_add(self, rhs: impl Into<Self>) -> Option<Self> {
         let rhs = rhs.into();
@@ -300,7 +300,7 @@ impl YearMonthDuration {
         })
     }
 
-    /// [op:subtract-yearMonthDurations](https://www.w3.org/TR/xpath-functions/#func-subtract-yearMonthDurations)
+    /// [op:subtract-yearMonthDurations](https://www.w3.org/TR/xpath-functions-31/#func-subtract-yearMonthDurations)
     #[inline]
     pub fn checked_sub(self, rhs: impl Into<Self>) -> Option<Self> {
         let rhs = rhs.into();
@@ -427,28 +427,28 @@ impl DayTimeDuration {
         }
     }
 
-    /// [fn:days-from-duration](https://www.w3.org/TR/xpath-functions/#func-days-from-duration)
+    /// [fn:days-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-days-from-duration)
     #[allow(clippy::cast_possible_truncation)]
     #[inline]
     pub fn days(&self) -> i64 {
         (self.seconds.as_i128() / 86400) as i64
     }
 
-    /// [fn:hours-from-duration](https://www.w3.org/TR/xpath-functions/#func-hours-from-duration)
+    /// [fn:hours-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-hours-from-duration)
     #[allow(clippy::cast_possible_truncation)]
     #[inline]
     pub fn hours(&self) -> i64 {
         ((self.seconds.as_i128() % 86400) / 3600) as i64
     }
 
-    /// [fn:minutes-from-duration](https://www.w3.org/TR/xpath-functions/#func-minutes-from-duration)
+    /// [fn:minutes-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-minutes-from-duration)
     #[allow(clippy::cast_possible_truncation)]
     #[inline]
     pub fn minutes(&self) -> i64 {
         ((self.seconds.as_i128() % 3600) / 60) as i64
     }
 
-    /// [fn:seconds-from-duration](https://www.w3.org/TR/xpath-functions/#func-seconds-from-duration)
+    /// [fn:seconds-from-duration](https://www.w3.org/TR/xpath-functions-31/#func-seconds-from-duration)
     #[inline]
     pub fn seconds(&self) -> Decimal {
         self.seconds.checked_rem(60).unwrap()
@@ -464,7 +464,7 @@ impl DayTimeDuration {
         self.seconds.to_be_bytes()
     }
 
-    /// [op:add-dayTimeDurations](https://www.w3.org/TR/xpath-functions/#func-add-dayTimeDurations)
+    /// [op:add-dayTimeDurations](https://www.w3.org/TR/xpath-functions-31/#func-add-dayTimeDurations)
     #[inline]
     pub fn checked_add(&self, rhs: impl Into<Self>) -> Option<Self> {
         let rhs = rhs.into();
@@ -473,7 +473,7 @@ impl DayTimeDuration {
         })
     }
 
-    /// [op:subtract-dayTimeDurations](https://www.w3.org/TR/xpath-functions/#func-subtract-dayTimeDurations)
+    /// [op:subtract-dayTimeDurations](https://www.w3.org/TR/xpath-functions-31/#func-subtract-dayTimeDurations)
     #[inline]
     pub fn checked_sub(&self, rhs: impl Into<Self>) -> Option<Self> {
         let rhs = rhs.into();
diff --git a/lib/oxsdatatypes/src/float.rs b/lib/oxsdatatypes/src/float.rs
index 29ebde30..7f7b979b 100644
--- a/lib/oxsdatatypes/src/float.rs
+++ b/lib/oxsdatatypes/src/float.rs
@@ -29,25 +29,25 @@ impl Float {
         self.value.to_be_bytes()
     }
 
-    /// [fn:abs](https://www.w3.org/TR/xpath-functions/#func-abs)
+    /// [fn:abs](https://www.w3.org/TR/xpath-functions-31/#func-abs)
     #[inline]
     pub fn abs(self) -> Self {
         self.value.abs().into()
     }
 
-    /// [fn:ceiling](https://www.w3.org/TR/xpath-functions/#func-ceiling)
+    /// [fn:ceiling](https://www.w3.org/TR/xpath-functions-31/#func-ceiling)
     #[inline]
     pub fn ceil(self) -> Self {
         self.value.ceil().into()
     }
 
-    /// [fn:floor](https://www.w3.org/TR/xpath-functions/#func-floor)
+    /// [fn:floor](https://www.w3.org/TR/xpath-functions-31/#func-floor)
     #[inline]
     pub fn floor(self) -> Self {
         self.value.floor().into()
     }
 
-    /// [fn:round](https://www.w3.org/TR/xpath-functions/#func-round)
+    /// [fn:round](https://www.w3.org/TR/xpath-functions-31/#func-round)
     #[inline]
     pub fn round(self) -> Self {
         self.value.round().into()
diff --git a/lib/oxsdatatypes/src/integer.rs b/lib/oxsdatatypes/src/integer.rs
index 0c9d90e5..d3b5fbc9 100644
--- a/lib/oxsdatatypes/src/integer.rs
+++ b/lib/oxsdatatypes/src/integer.rs
@@ -26,7 +26,7 @@ impl Integer {
         self.value.to_be_bytes()
     }
 
-    /// [op:numeric-add](https://www.w3.org/TR/xpath-functions/#func-numeric-add)
+    /// [op:numeric-add](https://www.w3.org/TR/xpath-functions-31/#func-numeric-add)
     #[inline]
     pub fn checked_add(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -34,7 +34,7 @@ impl Integer {
         })
     }
 
-    /// [op:numeric-subtract](https://www.w3.org/TR/xpath-functions/#func-numeric-subtract)
+    /// [op:numeric-subtract](https://www.w3.org/TR/xpath-functions-31/#func-numeric-subtract)
     #[inline]
     pub fn checked_sub(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -42,7 +42,7 @@ impl Integer {
         })
     }
 
-    /// [op:numeric-multiply](https://www.w3.org/TR/xpath-functions/#func-numeric-multiply)
+    /// [op:numeric-multiply](https://www.w3.org/TR/xpath-functions-31/#func-numeric-multiply)
     #[inline]
     pub fn checked_mul(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -50,7 +50,7 @@ impl Integer {
         })
     }
 
-    /// [op:numeric-divide](https://www.w3.org/TR/xpath-functions/#func-numeric-divide)
+    /// [op:numeric-divide](https://www.w3.org/TR/xpath-functions-31/#func-numeric-divide)
     #[inline]
     pub fn checked_div(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -58,7 +58,7 @@ impl Integer {
         })
     }
 
-    /// [op:numeric-mod](https://www.w3.org/TR/xpath-functions/#func-numeric-mod)
+    /// [op:numeric-mod](https://www.w3.org/TR/xpath-functions-31/#func-numeric-mod)
     #[inline]
     pub fn checked_rem(&self, rhs: impl Into<Self>) -> Option<Self> {
         Some(Self {
@@ -73,7 +73,7 @@ impl Integer {
         })
     }
 
-    /// [op:numeric-unary-minus](https://www.w3.org/TR/xpath-functions/#func-numeric-unary-minus)
+    /// [op:numeric-unary-minus](https://www.w3.org/TR/xpath-functions-31/#func-numeric-unary-minus)
     #[inline]
     pub fn checked_neg(&self) -> Option<Self> {
         Some(Self {
@@ -81,7 +81,7 @@ impl Integer {
         })
     }
 
-    /// [fn:abs](https://www.w3.org/TR/xpath-functions/#func-abs)
+    /// [fn:abs](https://www.w3.org/TR/xpath-functions-31/#func-abs)
     #[inline]
     pub const fn abs(&self) -> Self {
         Self {
diff --git a/lib/sparesults/README.md b/lib/sparesults/README.md
index 8cf6c3c7..73ccea36 100644
--- a/lib/sparesults/README.md
+++ b/lib/sparesults/README.md
@@ -9,9 +9,9 @@ Sparesults
 
 Sparesults is a set of parsers and serializers for [SPARQL](https://www.w3.org/TR/sparql11-overview/) query results formats.
 
-It supports [SPARQL Query Results XML Format (Second Edition)](http://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/2013/REC-sparql11-results-csv-tsv-20130321/).
+It supports [SPARQL Query Results XML Format (Second Edition)](https://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
 
-Support for [SPARQL-star](https://w3c.github.io/rdf-star/cg-spec/#query-result-formats) is also available behind the `rdf-star` feature.
+Support for [SPARQL-star](https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html#query-result-formats) is also available behind the `rdf-star` feature.
 
 This crate is intended to be a building piece for SPARQL client and server implementations in Rust like [Oxigraph](https://oxigraph.org).
 
diff --git a/lib/sparesults/src/lib.rs b/lib/sparesults/src/lib.rs
index b30c17f0..6229072e 100644
--- a/lib/sparesults/src/lib.rs
+++ b/lib/sparesults/src/lib.rs
@@ -23,7 +23,7 @@ use std::rc::Rc;
 #[derive(Eq, PartialEq, Debug, Clone, Copy, Hash)]
 #[non_exhaustive]
 pub enum QueryResultsFormat {
-    /// [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/)
+    /// [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/)
     Xml,
     /// [SPARQL Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/)
     Json,
@@ -133,7 +133,7 @@ impl QueryResultsFormat {
 /// Parsers for [SPARQL query](https://www.w3.org/TR/sparql11-query/) results serialization formats.
 ///
 /// It currently supports the following formats:
-/// * [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/) ([`QueryResultsFormat::Xml`](QueryResultsFormat::Xml)).
+/// * [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/) ([`QueryResultsFormat::Xml`](QueryResultsFormat::Xml)).
 /// * [SPARQL Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) ([`QueryResultsFormat::Json`](QueryResultsFormat::Json)).
 /// * [SPARQL Query Results TSV Format](https://www.w3.org/TR/sparql11-results-csv-tsv/) ([`QueryResultsFormat::Tsv`](QueryResultsFormat::Tsv)).
 ///
@@ -326,7 +326,7 @@ impl<R: BufRead> Iterator for SolutionsReader<R> {
 /// A serializer for [SPARQL query](https://www.w3.org/TR/sparql11-query/) results serialization formats.
 ///
 /// It currently supports the following formats:
-/// * [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/) ([`QueryResultsFormat::Xml`](QueryResultsFormat::Xml))
+/// * [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/) ([`QueryResultsFormat::Xml`](QueryResultsFormat::Xml))
 /// * [SPARQL Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) ([`QueryResultsFormat::Json`](QueryResultsFormat::Json))
 /// * [SPARQL Query Results CSV Format](https://www.w3.org/TR/sparql11-results-csv-tsv/) ([`QueryResultsFormat::Csv`](QueryResultsFormat::Csv))
 /// * [SPARQL Query Results TSV Format](https://www.w3.org/TR/sparql11-results-csv-tsv/) ([`QueryResultsFormat::Tsv`](QueryResultsFormat::Tsv))
diff --git a/lib/sparesults/src/xml.rs b/lib/sparesults/src/xml.rs
index d4973fdf..dbc17242 100644
--- a/lib/sparesults/src/xml.rs
+++ b/lib/sparesults/src/xml.rs
@@ -1,4 +1,4 @@
-//! Implementation of [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/)
+//! Implementation of [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/)
 
 use crate::error::{ParseError, SyntaxError};
 use oxrdf::vocab::rdf;
diff --git a/lib/spargebra/README.md b/lib/spargebra/README.md
index b2783605..275fb5f0 100644
--- a/lib/spargebra/README.md
+++ b/lib/spargebra/README.md
@@ -15,7 +15,7 @@ The emitted tree is based on [SPARQL 1.1 Query Algebra](https://www.w3.org/TR/sp
 
 The API entry point for SPARQL queries is the [`Query`] struct and the API entry point for SPARQL updates is the [`Update`] struct.
 
-Support for [SPARQL-star](https://w3c.github.io/rdf-star/cg-spec/#sparql-star) is also available behind the `rdf-star` feature.
+Support for [SPARQL-star](https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html#sparql-star) is also available behind the `rdf-star` feature.
 
 This crate is intended to be a building piece for SPARQL implementations in Rust like [Oxigraph](https://oxigraph.org).
 
diff --git a/lib/spargebra/src/algebra.rs b/lib/spargebra/src/algebra.rs
index e3dcbeb3..d694ba53 100644
--- a/lib/spargebra/src/algebra.rs
+++ b/lib/spargebra/src/algebra.rs
@@ -111,27 +111,27 @@ pub enum Expression {
     Equal(Box<Self>, Box<Self>),
     /// [sameTerm](https://www.w3.org/TR/sparql11-query/#func-sameTerm).
     SameTerm(Box<Self>, Box<Self>),
-    /// [op:numeric-greater-than](https://www.w3.org/TR/xpath-functions/#func-numeric-greater-than) and other XSD greater than operators.
+    /// [op:numeric-greater-than](https://www.w3.org/TR/xpath-functions-31/#func-numeric-greater-than) and other XSD greater than operators.
     Greater(Box<Self>, Box<Self>),
     GreaterOrEqual(Box<Self>, Box<Self>),
-    /// [op:numeric-less-than](https://www.w3.org/TR/xpath-functions/#func-numeric-less-than) and other XSD greater than operators.
+    /// [op:numeric-less-than](https://www.w3.org/TR/xpath-functions-31/#func-numeric-less-than) and other XSD greater than operators.
     Less(Box<Self>, Box<Self>),
     LessOrEqual(Box<Self>, Box<Self>),
     /// [IN](https://www.w3.org/TR/sparql11-query/#func-in)
     In(Box<Self>, Vec<Self>),
-    /// [op:numeric-add](https://www.w3.org/TR/xpath-functions/#func-numeric-add) and other XSD additions.
+    /// [op:numeric-add](https://www.w3.org/TR/xpath-functions-31/#func-numeric-add) and other XSD additions.
     Add(Box<Self>, Box<Self>),
-    /// [op:numeric-subtract](https://www.w3.org/TR/xpath-functions/#func-numeric-subtract) and other XSD subtractions.
+    /// [op:numeric-subtract](https://www.w3.org/TR/xpath-functions-31/#func-numeric-subtract) and other XSD subtractions.
     Subtract(Box<Self>, Box<Self>),
-    /// [op:numeric-multiply](https://www.w3.org/TR/xpath-functions/#func-numeric-multiply) and other XSD multiplications.
+    /// [op:numeric-multiply](https://www.w3.org/TR/xpath-functions-31/#func-numeric-multiply) and other XSD multiplications.
     Multiply(Box<Self>, Box<Self>),
-    /// [op:numeric-divide](https://www.w3.org/TR/xpath-functions/#func-numeric-divide) and other XSD divides.
+    /// [op:numeric-divide](https://www.w3.org/TR/xpath-functions-31/#func-numeric-divide) and other XSD divides.
     Divide(Box<Self>, Box<Self>),
-    /// [op:numeric-unary-plus](https://www.w3.org/TR/xpath-functions/#func-numeric-unary-plus) and other XSD unary plus.
+    /// [op:numeric-unary-plus](https://www.w3.org/TR/xpath-functions-31/#func-numeric-unary-plus) and other XSD unary plus.
     UnaryPlus(Box<Self>),
-    /// [op:numeric-unary-minus](https://www.w3.org/TR/xpath-functions/#func-numeric-unary-minus) and other XSD unary minus.
+    /// [op:numeric-unary-minus](https://www.w3.org/TR/xpath-functions-31/#func-numeric-unary-minus) and other XSD unary minus.
     UnaryMinus(Box<Self>),
-    /// [fn:not](https://www.w3.org/TR/xpath-functions/#func-not).
+    /// [fn:not](https://www.w3.org/TR/xpath-functions-31/#func-not).
     Not(Box<Self>),
     /// [EXISTS](https://www.w3.org/TR/sparql11-query/#func-filter-exists).
     Exists(Box<GraphPattern>),
@@ -577,7 +577,7 @@ pub enum GraphPattern {
         start: usize,
         length: Option<usize>,
     },
-    /// [Group](https://www.w3.org/TR/sparql11-federated-query/#aggregateAlgebra).
+    /// [Group](https://www.w3.org/TR/sparql11-query/#aggregateAlgebra).
     Group {
         inner: Box<Self>,
         variables: Vec<Variable>,
diff --git a/lib/src/io/format.rs b/lib/src/io/format.rs
index 67d7b8d5..7c95ddcb 100644
--- a/lib/src/io/format.rs
+++ b/lib/src/io/format.rs
@@ -1,4 +1,4 @@
-/// [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-graph) serialization formats.
+/// [RDF graph](https://www.w3.org/TR/rdf11-concepts/#dfn-rdf-graph) serialization formats.
 ///
 /// This enumeration is non exhaustive. New formats like JSON-LD will be added in the future.
 #[derive(Eq, PartialEq, Debug, Clone, Copy, Hash)]
diff --git a/server/README.md b/server/README.md
index 6bcf92b4..851d7521 100644
--- a/server/README.md
+++ b/server/README.md
@@ -27,7 +27,7 @@ It is also usable as [a Rust library](https://crates.io/crates/oxigraph) and as
 Oxigraph implements the following specifications:
 * [SPARQL 1.1 Query](https://www.w3.org/TR/sparql11-query/), [SPARQL 1.1 Update](https://www.w3.org/TR/sparql11-update/), and [SPARQL 1.1 Federated Query](https://www.w3.org/TR/sparql11-federated-query/).
 * [Turtle](https://www.w3.org/TR/turtle/), [TriG](https://www.w3.org/TR/trig/), [N-Triples](https://www.w3.org/TR/n-triples/), [N-Quads](https://www.w3.org/TR/n-quads/), and [RDF XML](https://www.w3.org/TR/rdf-syntax-grammar/) RDF serialization formats for both data ingestion and retrieval using the [Rio library](https://github.com/oxigraph/rio).
-* [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
+* [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/), [SPARQL 1.1 Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/) and [SPARQL 1.1 Query Results CSV and TSV Formats](https://www.w3.org/TR/sparql11-results-csv-tsv/).
 * [SPARQL 1.1 Protocol](https://www.w3.org/TR/sparql11-protocol/#query-operation) and [SPARQL 1.1 Graph Store HTTP Protocol](https://www.w3.org/TR/sparql11-http-rdf-update/).
 
 A preliminary benchmark [is provided](../bench/README.md).
@@ -55,7 +55,7 @@ It provides the following REST actions:
   curl -X POST -H 'Content-Type:application/sparql-query' \
     --data 'SELECT * WHERE { ?s ?p ?o } LIMIT 10' http://localhost:7878/query
   ```
-  This action supports content negotiation and could return [Turtle](https://www.w3.org/TR/turtle/), [N-Triples](https://www.w3.org/TR/n-triples/), [RDF XML](https://www.w3.org/TR/rdf-syntax-grammar/), [SPARQL Query Results XML Format](http://www.w3.org/TR/rdf-sparql-XMLres/) and [SPARQL Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/).
+  This action supports content negotiation and could return [Turtle](https://www.w3.org/TR/turtle/), [N-Triples](https://www.w3.org/TR/n-triples/), [RDF XML](https://www.w3.org/TR/rdf-syntax-grammar/), [SPARQL Query Results XML Format](https://www.w3.org/TR/rdf-sparql-XMLres/) and [SPARQL Query Results JSON Format](https://www.w3.org/TR/sparql11-results-json/).
 * `/update` allows to execute SPARQL updates against the server repository following the [SPARQL 1.1 Protocol](https://www.w3.org/TR/sparql11-protocol/#update-operation).
   For example:
   ```sh
@@ -244,7 +244,7 @@ WantedBy=multi-user.target
 ### From 0.2 to 0.3
 * The cli API has been completely rewritten. To start the server run `oxigraph_server serve --location MY_STORAGE` instead of `oxigraph_server --file MY_STORAGE`.
 * Fast data bulk loading is not supported using `oxigraph_server load --location MY_STORAGE --file MY_FILE`. The file format is guessed from the extension (`.nt`, `.ttl`, `.nq`...).
-* [RDF-star](https://w3c.github.io/rdf-star/cg-spec) is now implemented.
+* [RDF-star](https://w3c.github.io/rdf-star/cg-spec/2021-12-17.html) is now implemented.
 * All operations are now transactional using the "repeatable read" isolation level:
   the store only exposes changes that have been "committed" (i.e. no partial writes)
   and the exposed state does not change for the complete duration of a read operation (e.g. a SPARQL query) or a read/write operation (e.g. a SPARQL update).
diff --git a/test_spec_links.py b/test_spec_links.py
new file mode 100644
index 00000000..bfc156e0
--- /dev/null
+++ b/test_spec_links.py
@@ -0,0 +1,57 @@
+import re
+import sys
+from pathlib import Path
+from urllib.error import HTTPError
+from urllib.parse import urlsplit, urlunsplit
+from urllib.request import urlopen
+
+LINK_REGEXES = {
+    r"\[[^]]+]\((https?://(w3c.github.io|www.w3.org)/[^)]+)\)",  # Markdown
+    r"<(https?://(w3c.github.io|www.w3.org)/[^>]+)>`_",  # reStructuredText
+}
+
+base_path = Path(__file__).parent
+spec_cache = {}
+errors = set()
+
+for ext in ("md", "rs"):
+    for file in Path(__file__).parent.rglob(f"*.{ext}"):
+        content = file.read_text()
+        for link_regex in LINK_REGEXES:
+            for m in re.finditer(link_regex, content):
+                url = m.group(1)
+                (scheme, host, path, query, fragment) = urlsplit(url)
+                if scheme != "https":
+                    errors.add(f"HTTP URL used by {url} in {file}")
+                if query != "":
+                    errors.add(f"URL query used by {url} in {file}")
+                if path.endswith(".html/"):
+                    errors.add(f".html/ used by {url} in {file}")
+                base_url = urlunsplit(("https", host, path.rstrip("/"), "", ""))
+                if base_url not in spec_cache:
+                    try:
+                        with urlopen(base_url) as response:
+                            spec_cache[base_url] = response.read().decode()
+                    except HTTPError as e:
+                        errors.add(
+                            f"Fetching {url} used in {file} return HTTP error: {e}"
+                        )
+                spec_content = spec_cache.get(base_url, "")
+                if (
+                    fragment != ""
+                    and re.search(rf"[iI][dD]\s*=\s*['\"]{fragment}['\"]", spec_content)
+                    is None
+                ):
+                    errors.add(
+                        f"Fragment {fragment} of {url} used in {file} does not exist"
+                    )
+
+print("Used specs:")
+for url in sorted(spec_cache.keys()):
+    print(url)
+
+if errors:
+    print()
+    for error in sorted(errors):
+        print(error, file=sys.stderr)
+    exit(1)