Cita APA (7a ed.)

(2006). Longman language activator: Helps you write and speak natural English (new ed.). Longman.

Cita Chicago Style (17a ed.)

Longman Language Activator: Helps You Write and Speak Natural English. new ed. Harlow: Longman, 2006.

Cita MLA (9a ed.)

Longman Language Activator: Helps You Write and Speak Natural English. new ed. Longman, 2006.