Cita APA (7a ed.)

Mackenzie, M. M. (1981). Using essential english tenses: Intermediate level (9th impression.). Evans Brothers.

Cita Chicago Style (17a ed.)

Mackenzie, M.D. Munro. Using Essential English Tenses: Intermediate Level. 9th impression. London: Evans Brothers, 1981.

Cita MLA (9a ed.)

Mackenzie, M.D. Munro. Using Essential English Tenses: Intermediate Level. 9th impression. Evans Brothers, 1981.