APA (7th ed.) Citation

Dahl, R., & Blake, Q. (2001). George's marvellous medicine. Puffin Books.

Chicago Style (17th ed.) Citation

Dahl, Roald, and Quentin Blake. George's Marvellous Medicine. London: Puffin Books, 2001.

MLA (9th ed.) Citation

Dahl, Roald, and Quentin Blake. George's Marvellous Medicine. Puffin Books, 2001.