APA (7th ed.) Citation

Walker, R. (2011). What is the theory of evolution? Crabtree Pub..

Chicago Style (17th ed.) Citation

Walker, Robert. What Is the Theory of Evolution? New York, N.Y.: Crabtree Pub., 2011.

MLA (8th ed.) Citation

Walker, Robert. What Is the Theory of Evolution? Crabtree Pub., 2011.

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