Question: For which country did Alexander Lippisch design airplanes?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/designer> <http://dbpedia.org/resource/Alexander_Lippisch> . ?x <http://dbpedia.org/property/nationalOrigin> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Aircraft>}