Who gave the voice to the characters sculpted by Clamp?
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/creator> <http://dbpedia.org/resource/Clamp_(manga_artists)> . ?x <http://dbpedia.org/ontology/voice> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/FictionalCharacter>}
Clamp_(manga_artists)