query: SELECT ?item ?nr_s ?delabel WHERE {
    ?item wdt:P31 wd:Q21191270.
    ?item p:P179 ?series_statement.
    ?series_statement ps:P179 wd:Q708661.
    ?series_statement pq:P1545 ?nr_s.
    ?item rdfs:label ?delabel.
    FILTER((LANG(?delabel)) = "de")  
  } ORDER BY xsd:integer(?nr_s)