Question: Name all the doctoral student of the scientist who also supervised Mary Ainsworth ?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/doctoralStudents> <http://dbpedia.org/resource/Mary_Ainsworth> . ?x <http://dbpedia.org/property/doctoralStudents> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Scientist>}