test

CONSTRUCT {?concept a skos:Concept .
           ?concept skos:prefLabel ?label .
           ?concept skos:notation ?identifier .
           }
WHERE {
  ?concept a skos:Concept . 
  OPTIONAL { ?resource2 a gpml:requiresCurationAttention . FILTER(?resource2 = ?concept) }
  FILTER(!bound(?resource2))
  ?concept rdfs:label ?label .
  ?concept dc:identifier ?identifier.
}