What is the birth place of the astronaut whose mission was the Vostok programmer?
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/mission> <http://dbpedia.org/resource/Vostok_programme> . ?x <http://dbpedia.org/ontology/birthPlace> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Astronaut>}
Vostok_programme