Question: Which house has published books about Jazz?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/ontology/nonFictionSubject> <http://dbpedia.org/resource/Jazz> . ?x <http://dbpedia.org/ontology/publisher> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Book>}