APA (7th ed.) Citation

Hawking, L. (2008). George's secret key to the universe. Corgi Books.

Chicago Style (17th ed.) Citation

Hawking, Lucy. George's Secret Key to the Universe. London: Corgi Books, 2008.

MLA (9th ed.) Citation

Hawking, Lucy. George's Secret Key to the Universe. Corgi Books, 2008.

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