Question: Name the rivers which originate from within Pittsburg?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/cities> <http://dbpedia.org/resource/Pittsburg,_New_Hampshire> . ?uri <http://dbpedia.org/ontology/source> ?x  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/River>}