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SELECT * from named <https://unstats.un.org/classifications/CPC/v2.1/> {
  GRAPH ?g { ?s ?p ?o }.
}

Get al items in 

SELECT ?collection_code ?concept_code ?concept_label  WHERE {
    ?collection skos:notation ?collection_code . FILTER (str(?collection_code)='fisheries') .
    ?collection skos:member ?concept .
    ?concept skos:notation ?concept_code .
    ?concept skos:prefLabel ?concept_label .
}

On concept schemes

Get all skos:ConceptScheme in a repo

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