APA

Widdowson H., . (2002). Linguistics. New York: Oxford University Press.

Chicago

Widdowson H.G, . 2002. Linguistics. New York: Oxford University Press.

Harvard

Widdowson H., . (2002). Linguistics. New York: Oxford University Press.

MLA

Widdowson H.G, . Linguistics. New York: Oxford University Press. 2002.