APA (7th ed.) Citation

Koestler, A. (1973). Darkness at noon. Penguin Books.

Chicago Style (17th ed.) Citation

Koestler, Arthur. Darkness at Noon. Harmondsworth: Penguin Books, 1973.

MLA (8th ed.) Citation

Koestler, Arthur. Darkness at Noon. Penguin Books, 1973.

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