APA

Kerr P., . (2005). Straightforward. Pre-intermediate. Oxford: Macmillan.

Chicago

Kerr P, . 2005. Straightforward. Pre-intermediate. Oxford: Macmillan.

Harvard

Kerr P., . (2005). Straightforward. Pre-intermediate. Oxford: Macmillan.

MLA

Kerr P, . Straightforward. Pre-intermediate. Oxford: Macmillan. 2005.