SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/sourceRegion> <http://dbpedia.org/resource/Greater_London> . ?x <http://dbpedia.org/property/mouthLocation> ?uri . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/River>}
Where do the rivers from greater London flow into?
SELECT DISTINCT ?o WHERE { ?w rdf:type ontology:River . ?w property:source_region resource:Greater_London . ?w property:mouth_location ?o }
River Crane, London, Brentford, River Thames, Petersham, London, Barn Elms
The mouths of the rivers whose source is in Greater London are [River Crane, London, Brentford, River Thames, Petersham, London, Barn Elms].
River estuaries originating in Greater London: [River Hebe, London, Brentford, Thames, Hebham, London, Barn Elms].