Question: Which river's mouth is located in Gulf of Mexico and has source location as Itasca State Park ?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT ?uri WHERE {?uri onto:riverMouth <http://dbpedia.org/resource/Gulf_of_Mexico> . ?uri prop:sourceLocation <http://dbpedia.org/resource/Itasca_State_Park>  . ?uri rdf:type onto:River}