What is the {railway company} for {operator} of {Gotthard Base Tunnel}
What railway company operates the Gotthard Base Tunnel?
 select distinct ?obj where { wd:Q193002 wdt:P137 ?obj . ?obj wdt:P31 wd:Q249556 } 
select distinct ?obj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q193002> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P137> . ?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/Q249556> } 
What railroad company works the Gotthard Base Tunnel?