Webster, D. (1981). Keep listening: Study guide (1a. ed.). Longman.
Chicago-čujuhus (17. p.)Webster, Diana. Keep Listening: Study Guide. 1a. ed. Harlow: Longman, 1981.
MLA-čujuhus (9. p.)Webster, Diana. Keep Listening: Study Guide. 1a. ed. Longman, 1981.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.