International Federation for Documetation, Classification Research. (2021). International Classification. Verlag Dokumentation.
Chicago-referens (17:e uppl.)International Federation for Documetation, Classification Research. International Classification. Munchen, Alemanha: Verlag Dokumentation, 2021.
MLA-referens (8:e uppl.)International Federation for Documetation, Classification Research. International Classification. Verlag Dokumentation, 2021.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.