query: SELECT ?region ?regionLabel ?isoCode ?geonamesID
  WHERE 
  {
    ?region wdt:P1566 "863904" .
    ?region wdt:P1566 ?geonamesID 
    OPTIONAL{
      ?region wdt:P300 ?isoCode .
    }
    SERVICE wikibase:label {
      bd:serviceParam wikibase:language "en" .
    }
  }