query: SELECT DISTINCT ?districtALabel ?districtBLabel WHERE {
    ?districtA wdt:P31 wd:Q261023;
               wdt:P1545 ?districtANr.
    ?districtB wdt:P31 wd:Q261023;
               wdt:P1545 ?districtBNr.
    ?districtA wdt:P47 ?districtB.
    FILTER NOT EXISTS {
      ?line wdt:P361 wd:Q129612; 
            wdt:P131 ?districtA, ?districtB.
    }
    FILTER (?districtANr < ?districtBNr)
    SERVICE wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE]". }
  }
  ORDER BY xsd:integer(?districtANr) xsd:integer(?districtBNr)