Question: Which European countries are a constitutional monarchy?
SPARQL:
PREFIX onto: <http://dbpedia.org/ontology/>
PREFIX yago: <http://dbpedia.org/class/yago/>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX res: <http://dbpedia.org/resource/>
SELECT DISTINCT ?uri ?string
WHERE 
{
	?uri rdf:type yago:EuropeanCountries .
        ?uri onto:governmentType res:Constitutional_monarchy .
        OPTIONAL {?uri rdfs:label ?string. FILTER (lang(?string) = 'en') }
}