What is the {tower station} for {owned by} of {Amtrak}
[]
Amtrak is the owner of which tower station ?
SELECT DISTINCT ?r WHERE { ?r rdf:type ontology:tower_station . ?r property:owned_by resource:Amtrak }
select distinct ?subj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?subj . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P127> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q23239> . ?subj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q55484> } 
 select distinct ?sbj where { ?sbj wdt:P127 wd:Q23239 . ?sbj wdt:P31 wd:Q55484 } 
30th Street Station