APA (7th ed.) Citation

FEST, Richard, & Winston. (1973). Hitler. Penguin Books.

Chicago Style (17th ed.) Citation

FEST, Richard, and Winston. Hitler. London: Penguin Books, 1973.

MLA (8th ed.) Citation

FEST, et al. Hitler. Penguin Books, 1973.

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