APA (7th ed.) Citation

Azar, B. S., & Hagen, S. A. (2009). Understanding and using english grammar (4th ed.). Pearson.

Chicago Style (17th ed.) Citation

Azar, Betty S., and Stacy A. Hagen. Understanding and Using English Grammar. 4th ed. New York: Pearson, 2009.

MLA (9th ed.) Citation

Azar, Betty S., and Stacy A. Hagen. Understanding and Using English Grammar. 4th ed. Pearson, 2009.