APA
Martin B., . (2004). Polar bear, polar bear, what do you hear?. New York: H. Holt.
Chicago
Martin Bill, . 2004. Polar bear, polar bear, what do you hear?. New York: H. Holt.
Harvard
Martin B., . (2004). Polar bear, polar bear, what do you hear?. New York: H. Holt.
MLA
Martin Bill, . Polar bear, polar bear, what do you hear?. New York: H. Holt. 2004.