Question: Who collaborated with Johnny Cash and Kris Kristofferson ?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?uri <http://dbpedia.org/property/associatedActs> <http://dbpedia.org/resource/Johnny_Cash> . ?uri <http://dbpedia.org/property/associatedActs> <http://dbpedia.org/resource/Kris_Kristofferson> . }