APA (7. basım) Alıntı

Guffey, M. E. (2005). Professional English. Thomson/South-Western.

Chicago Style (17. basım) Atıf

Guffey, Mary Ellen. Professional English. Australia: Thomson/South-Western, 2005.

MLA (9th ed.) Atıf

Guffey, Mary Ellen. Professional English. Thomson/South-Western, 2005.