APA (7e ed.) Bronvermelding

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

Chicago (17e ed.) Bronvermelding

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

MLA (9e ed.) Bronvermelding

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