What is the {world war} for {time period} of {Battle of the Bulge}
when did the Battle of the Bulge break out?
When was the Battle of the Bulge?
SELECT DISTINCT ?e WHERE { ?e rdf:type ontology:world_war . resource:Battle_of_the_Bulge property:time_period ?e }
select distinct ?obj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q151018> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P2348> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj . ?obj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q103495> } 
 select distinct ?obj where { wd:Q151018 wdt:P2348 ?obj . ?obj wdt:P31 wd:Q103495 } 
World War II