Name the sea located near Europe and has a nearby city as Rostock ?
SELECT DISTINCT ?uri WHERE {?uri <http://dbpedia.org/property/cities> <http://dbpedia.org/resource/Rostock> . ?uri <http://dbpedia.org/ontology/location> <http://dbpedia.org/resource/Europe>  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Sea>}
Rostock Europe