APA (7th ed.) Citation

Sproul, R. C. (2003). Defending your Faith: An introduction to apologetics. Crossway.

Chicago Style (17th ed.) Citation

Sproul, R. C. Defending Your Faith: An Introduction to Apologetics. Wheaton, IL: Crossway, 2003.

MLA (9th ed.) Citation

Sproul, R. C. Defending Your Faith: An Introduction to Apologetics. Crossway, 2003.