Who are the members of organizations headquartered at Amstelveen?
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/headquarters> <http://dbpedia.org/resource/Amstelveen> . ?x <http://dbpedia.org/property/membership> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Organisation>}
Amstelveen