APA (7th ed.) Citation

Willems, M., & Muth, J. J. (2010). City Dog, Country Frog. Hyperion Books for Children.

Chicago Style (17th ed.) Citation

Willems, Mo, and Jon J. Muth. City Dog, Country Frog. New York: Hyperion Books for Children, 2010.

MLA (8th ed.) Citation

Willems, Mo, and Jon J. Muth. City Dog, Country Frog. Hyperion Books for Children, 2010.