APA (7th ed.) Citation

Wellisch, H. (1970). The Universal Decimal Classification; A Programmed Instruction Course.

Chicago Style (17th ed.) Citation

Wellisch, Hans. The Universal Decimal Classification; A Programmed Instruction Course. 1970.

MLA (9th ed.) Citation

Wellisch, Hans. The Universal Decimal Classification; A Programmed Instruction Course. 1970.

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