UDC Kaynakları:
- UDC Consorsium: http://www.udcc.org/
- UDC Summary: http://www.udcc.org/udcsummary/php/index.php?lang=tr&pr=Y
- UDCS Linked Data: http://udcdata.info/
- UDC Blog: http://universaldecimalclassification.blogspot.com/
- Twitter: @UDCC
- Universal Decimal Classification: http://www.princeton.edu/~achaney/tmve/wiki100k/docs/Universal_Decimal_Classification.html
- Kısa liste: https://www.unido.org/library/help/udc.html
- Liste: https://globaljournals.org/GJPortal/udc/menu-id-1273
- Vikipedi: http://en.wikipedia.org/wiki/Universal_Decimal_Classification
Numaralar
- International Standard Book Number (ISBN)
- International Standard Serial Number (ISSN)
