Question: Name the president whose had relatives in Clinton family and lieutenant named Joe Purcell?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT ?uri WHERE {?uri onto:relation <http://dbpedia.org/resource/Clinton_family> . ?uri onto:lieutenant <http://dbpedia.org/resource/Joe_Purcell>  . ?uri rdf:type onto:President}