Cita APA (7a ed.)

Tufnell, M. (2006). Intelligent Business: Upper intermediate business english. Longman.

Cita Chicago Style (17a ed.)

Tufnell, Mark. Intelligent Business: Upper Intermediate Business English. London: Longman, 2006.

Cita MLA (9a ed.)

Tufnell, Mark. Intelligent Business: Upper Intermediate Business English. Longman, 2006.