Question: Georg Meissner was doctoral supervisor of which scientist ?
SPARQL:
SELECT DISTINCT ?uri WHERE {?uri <http://dbpedia.org/property/doctoralAdvisor> <http://dbpedia.org/resource/Georg_Meissner>  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Scientist>}