Question: Give me all ESA astronauts.
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 
PREFIX onto: <http://dbpedia.org/ontology/> 
PREFIX res: <http://dbpedia.org/resource/> 
SELECT DISTINCT ?uri 
WHERE { 
        ?uri rdf:type onto:Astronaut . 
        ?uri onto:type res:European_Space_Agency .
}