Question: What is the nationality of the J. T. Krogh which is also the  sovereign state of the Camilla Martin
SPARQL:
SELECT DISTINCT ?uri WHERE { <http://dbpedia.org/resource/J._T._Krogh> <http://dbpedia.org/ontology/nationality> ?uri. <http://dbpedia.org/resource/Camilla_Martin> <http://dbpedia.org/ontology/country> ?uri}