International Federation for Documetation, Classification Research. (2021). International Classification. Verlag Dokumentation.
Chicago-viite (17. p.)International Federation for Documetation, Classification Research. International Classification. Munchen, Alemanha: Verlag Dokumentation, 2021.
MLA-viite (8. p.)International Federation for Documetation, Classification Research. International Classification. Verlag Dokumentation, 2021.
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