What is {perpetrator} of {Vietnam War}, that has {president} is {Mao Zedong} ?
What country's leader was Mao Zedong that started the Vietnam War?
SELECT ?l WHERE { resource:Vietnam_War property:participant ?l . ?l property:head_of_state resource:Mao_Zedong }
SELECT ?answer WHERE { ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q8740> . ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P710>. ?statement1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?answer . ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?answer. ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P35> . ?statement2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q5816> . }
SELECT ?answer WHERE { wd:Q8740 wdt:P710 ?answer . ?answer wdt:P35 wd:Q5816}