Question: Which companies are located in California, USA?
SPARQL query:
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX onto: <http://dbpedia.org/ontology/>
PREFIX res: <http://dbpedia.org/resource/>
SELECT DISTINCT ?uri ?string
WHERE
{ 
	?uri rdf:type onto:Organisation .
        ?uri onto:location res:California .
        OPTIONAL {?uri rdfs:label ?string . FILTER (lang(?string) = 'en') }
}