Question: Which university attended by Donn Barber and education institute of Jack McGregor ?
SPARQL:
 SELECT DISTINCT ?uri WHERE { <http://dbpedia.org/resource/Donn_Barber> <http://dbpedia.org/property/education> ?uri. <http://dbpedia.org/resource/Jack_McGregor> <http://dbpedia.org/ontology/education> ?uri}