Gaya APA

Azar, B, S., Hagen, S, A. (2009). Understanding and useing english grammar (4). USA: Pearson Longman.

Gaya MLA

Azar, Betty, S.., Hagen, Stacy, A.. "Understanding and useing english grammar". 4 USA: Pearson Longman, 2009. Buku Pend. Bahasa Inggris.