query: #Cathedrals in Paris
  #added before 2016-10
  
  SELECT DISTINCT ?item ?itemLabel ?inception
  WHERE
  {
    ?item wdt:P31 wd:Q46169 .
    ?item wdt:P17 wd:Q145 .
    OPTIONAL { ?item wdt:P571 ?inception . }
    
    SERVICE wikibase:label { bd:serviceParam wikibase:language "en". }
  } ORDER BY ?itemLabel