What is the {history of a city} for {history of topic} of {Istanbul}
What is the history topic of history city of Istanbul?
 select distinct ?obj where { wd:Q406 wdt:P2184 ?obj . ?obj wdt:P31 wd:Q28747937 } 
select distinct ?obj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q406> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P2184> . ?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/Q28747937> } 
What is the history subject of history city of Istanbul?