Cita APA (7a ed.)

(2010). Longman Language Activator (1st, 10th impr.). Longman.

Cita Chicago Style (17a ed.)

Longman Language Activator. 1st, 10th impr. Harlow: Longman, 2010.

Cita MLA (9a ed.)

Longman Language Activator. 1st, 10th impr. Longman, 2010.