Cita APA (7a ed.)

Webster, D. (1981). Keep listening: Study guide (1a. ed.). Longman.

Cita Chicago Style (17a ed.)

Webster, Diana. Keep Listening: Study Guide. 1a. ed. Harlow: Longman, 1981.

Cita MLA (9a ed.)

Webster, Diana. Keep Listening: Study Guide. 1a. ed. Longman, 1981.