Question: What writers have nationality as Statelessness?  
SPARQL:
SELECT DISTINCT ?uri WHERE {?uri <http://dbpedia.org/property/nationality> <http://dbpedia.org/resource/Statelessness> . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Writer>}