Question: Tell me the number of writers whose works have been recorded in Criteria Studios?
SPARQL:
SELECT DISTINCT COUNT(?uri) WHERE { ?x <http://dbpedia.org/ontology/recordedIn> <http://dbpedia.org/resource/Criteria_Studios> . ?x <http://dbpedia.org/property/writer> ?uri  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Artist>}