APA (7th ed.) Citation

Wells, D. (1986). The penguin dictionary of curious and interesting numbers. Penguin Books.

Chicago Style (17th ed.) Citation

Wells, David. The Penguin Dictionary of Curious and Interesting Numbers. Harmondsworth, England: Penguin Books, 1986.

MLA (9th ed.) Citation

Wells, David. The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, 1986.