APA (7th ed.) Citation

Tully, J., Gray, M., & Gray, G. (1980). Cats in the dark. Collins ELT.

Chicago Style (17th ed.) Citation

Tully, John, Maureen Gray, and Gordon Gray. Cats in the Dark. London [etc.]: Collins ELT, 1980.

MLA (9th ed.) Citation

Tully, John, et al. Cats in the Dark. Collins ELT, 1980.