Who has stock in the railway lines managed by Norfolk Southern Railway?
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/system> <http://dbpedia.org/resource/Norfolk_Southern_Railway> . ?x <http://dbpedia.org/property/owner> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/RailwayLine>}
Norfolk_Southern_Railway