APA

Oxenden C., . (2008). American english file. New York, USA: Oxford universoty press.

Chicago

Oxenden Clive, . 2008. American english file. New York, USA: Oxford universoty press.

Harvard

Oxenden C., . (2008). American english file. New York, USA: Oxford universoty press.

MLA

Oxenden Clive, . American english file. New York, USA: Oxford universoty press. 2008.