Question: What cities are around the valley bordering Lake Mead?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT ?uri WHERE { ?x onto:border <http://dbpedia.org/resource/Lake_Mead> . ?x onto:city ?uri . ?x rdf:type onto:Valley}