Question: Which monarchs were married to a German?
SPARQL query:
PREFIX onto: <http://dbpedia.org/ontology/>
PREFIX res: <http://dbpedia.org/resource/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
SELECT DISTINCT ?uri 
WHERE {
        ?uri rdf:type onto:Monarch . 
        ?uri onto:spouse ?spouse .
      { ?spouse onto:birthPlace res:Germany. }
      UNION 
      { ?spouse onto:birthPlace ?p . 
        ?p onto:country res:Germany. }
}