oxigraph/testsuite/oxigraph-tests/sparql-results/duplicated_variables.srj

{
  "head": {
    "vars": ["s", "p", "s"]
  },
  "results": {
    "bindings": [
      {
        "s": {
          "type": "uri",
          "value": "http://example.org/s1"
        }
      }
    ]
  }
}