Gaya APA

S, A., A, H. (2009). UNDERSTANDING AND USING ENGLISH GRAMMAR FOURTH EDITION WITH ANSWER KEY (Cet.. 2009). New York: PEARSON LONGMAN.

Gaya MLA

S, AZAR,BETTY., A, HAGEN,STACEY. "UNDERSTANDING AND USING ENGLISH GRAMMAR FOURTH EDITION WITH ANSWER KEY". Cet.. 2009 New York: PEARSON LONGMAN, 2009. Text.