SELECT * 
WHERE { ?location <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://www.w3.org/2006/vcard/ns#Location> . 
		 OPTIONAL{ ?location <http://www.w3.org/2006/vcard/ns#longitude> ?long . } 
		 OPTIONAL{ ?location <http://www.w3.org/2006/vcard/ns#latitude> ?lat . } 
			 }