SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/outflow> <http://dbpedia.org/resource/Congo_River> . ?x <http://dbpedia.org/ontology/outflow> ?uri . }
What are the outflow of the lakes which also has one of the outflow as Congo River?
SELECT DISTINCT ?r WHERE { ?o property:outflow resource:Congo_River . ?o property:outflow ?r . }
Nile, Congo River, BenuÃ© River, Zambezi
The outflows of the lakes whose one of the outflow is Congo River are [Nile, Congo River, BenuÃ© River, Zambezi].
[Nile, Congo River, Benoit River, Zambezi] are the outflow of the lakes which also has one of the outflow as Congo River.