APA (7th ed.) Citation

Walliams, D., & Blake, Q. (2009). The boy in the dress. HarperCollins Children's Books.

Chicago Style (17th ed.) Citation

Walliams, David, and Quentin Blake. The Boy in the Dress. London: HarperCollins Children's Books, 2009.

MLA (9th ed.) Citation

Walliams, David, and Quentin Blake. The Boy in the Dress. HarperCollins Children's Books, 2009.

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