APA (7th ed.) Citation

British Standards Institution, L. (1961). Universal decimal classification: Abridged English edition. The author.

Chicago Style (17th ed.) Citation

British Standards Institution, London. Universal Decimal Classification: Abridged English Edition. The author, 1961.

MLA (9th ed.) Citation

British Standards Institution, London. Universal Decimal Classification: Abridged English Edition. The author, 1961.

Warning: These citations may not always be 100% accurate.