PREFIX   ex:  <http://example.org/x/>
PREFIX  rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs:  <http://www.w3.org/2000/01/rdf-schema#>
PREFIX owl: <http://www.w3.org/2002/07/owl#>

SELECT ?x ?c
WHERE { 
?x rdf:type ?c . 
?c rdfs:subClassOf ex:c . 
?x ex:p _:y . 

}
