What is {employer} of {Georges Dumézil} that is {position held} is {professor} ?
When Georges Dumezil was a professor, who was his employer?
Who is the employer of Georges Dumezil when he was a professor?
SELECT ?q WHERE { resource:Georges_Dumézil property:employer ?j . ?j property:position_held resource:professor . ?j property:employer ?q }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q310590> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P108> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P39> <http://wikidata.dbpedia.org/resource/Q121594>
} 

SELECT ?obj WHERE { wd:Q310590 p:P108 ?s . ?s ps:P108 ?obj . ?s pq:P39 wd:Q121594 }