APA (7th ed.) Citation

Barker, R. E., & Davies, G. R. (1966). Books are different. Macmillan.

Chicago Style (17th ed.) Citation

Barker, R. E., and G. R. Davies. Books Are Different. London: Macmillan, 1966.

MLA (9th ed.) Citation

Barker, R. E., and G. R. Davies. Books Are Different. Macmillan, 1966.