La requête :

PREFIX dbo: <http://dbpedia.org/ontology/>
PREFIX dbr: <http://dbpedia.org/resource/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
PREFIX owl: <http://www.w3.org/2002/07/owl#>

SELECT DISTINCT ?value ?name ?wd where {
    {
      ?value rdf:type dbo:Writer .
    } 
    UNION {
       ?value dbo:occupation dbr:Writer.
    }
    ?value foaf:name ?name ;
           dbo:birthPlace ?birthplace ;
           owl:sameAs ?wd.
     ?birthplace dbo:country dbr:United_States .
     FILTER (regex(str(?wd),"wikidata.org"))
}