query: SELECT ?item ?nr_all ?release_ja ?release_de (GROUP_CONCAT(DISTINCT ?delabel) AS ?delabels) WHERE {
    ?item wdt:P31/wdt:P279* wd:Q21191270 .
    ?item p:P179 ?series_statement .
    ?series_statement ps:P179 wd:Q1564651 .
    ?series_statement pq:P1545 ?nr_all .  
      OPTIONAL {
    ?item p:P577 ?release_statement1 .
    ?release_statement1 ps:P577 ?release_ja .
    ?release_statement1 pq:P291 wd:Q17 .  
    ?item p:P577 ?release_statement2 .
    ?release_statement2 ps:P577 ?release_de .
    ?release_statement2 pq:P291 wd:Q183 .  
        }
    OPTIONAL {
      ?item rdfs:label ?delabel.
      FILTER((LANG(?delabel)) = "de")
    }
  }
  GROUP BY ?item ?nr_all ?release_ja ?release_de 
  ORDER BY xsd:integer(?nr_all)