APA

Azar B. S., Matthies B. F. & Hartle S. (2001). Understanding and using English grammar. [London?]: Longman.

Chicago

Azar B S, Matthies B F and Hartle S. 2001. Understanding and using English grammar. [London?]: Longman.

Harvard

Azar B. S., Matthies B. F. and Hartle S. (2001). Understanding and using English grammar. [London?]: Longman.

MLA

Azar B S, Matthies B F and Hartle S. Understanding and using English grammar. [London?]: Longman. 2001.