APA (7th ed.) Citation

English Language Book Society, Williams, W. D., & Marshall, A. J. (1972). Textbook of zoology (ELBS ed. of 7th ed.). English Language Book Society/Macmillan.

Chicago Style (17th ed.) Citation

English Language Book Society, W. D. Williams, and A. J. Marshall. Textbook of Zoology. ELBS ed. of 7th ed. London: English Language Book Society/Macmillan, 1972.

MLA (9th ed.) Citation

English Language Book Society, et al. Textbook of Zoology. ELBS ed. of 7th ed. English Language Book Society/Macmillan, 1972.