which rivers flow into a german lake?
SELECT DISTINCT ?uri WHERE { ?uri a <http://dbpedia.org/ontology/River> . ?x <http://dbpedia.org/ontology/inflow> ?uri ; a <http://dbpedia.org/ontology/Lake> ; <http://dbpedia.org/ontology/country> <http://dbpedia.org/resource/Germany> }
Germany