APA

Hashemi L., Thomas B., . (2003). Objective PET. Student's Book. : Cambridge University Press.

Chicago

Hashemi L, Thomas B, . 2003. Objective PET. Student's Book. : Cambridge University Press.

Harvard

Hashemi L., Thomas B., . (2003). Objective PET. Student's Book. : Cambridge University Press.

MLA

Hashemi L, Thomas B, . Objective PET. Student's Book. : Cambridge University Press. 2003.