Gaya APA

Azar, B, S., Hagen, , S, A. (2006). Basic English grammar : with answer key (3rd ed). New York: Pearson Education.

Gaya MLA

Azar, Betty, Schramfer., Hagen, , Stancy, A.. "Basic English grammar : with answer key". 3rd ed New York: Pearson Education, 2006. Text.