Question: Which sea is surrounded by Rostock and Kaliningrad?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT ?uri WHERE { ?uri prop:cities <http://dbpedia.org/resource/Rostock> . ?uri prop:cities <http://dbpedia.org/resource/Kaliningrad> . ?uri rdf:type onto:Sea}