APA (7th ed.) Citation

Walliams, D., & Ross, T. (2011). Billionaire boy. HarperCollins Children's Books.

Chicago Style (17th ed.) Citation

Walliams, David, and Tony Ross. Billionaire Boy. London: HarperCollins Children's Books, 2011.

MLA (9th ed.) Citation

Walliams, David, and Tony Ross. Billionaire Boy. HarperCollins Children's Books, 2011.

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