query: #Tractats
  SELECT ?tractat ?tractatLabel ?data
  WHERE {
      ?tractat wdt:P31*/wdt:P279* wd:Q131569 .
      ?tractat wdt:P585 ?data .
      SERVICE wikibase:label {bd:serviceParam wikibase:language "ca,en" .}
      FILTER (YEAR(?data) >= 1800)
    	FILTER (YEAR(?data) < 1900)
   }
  ORDER BY ASC(?data)