Berg, F. S. (1978). Listening and speech training package. Grune & Stratton.
Dyfyniad Arddull ChicagoBerg, Frederick S. Listening and Speech Training Package. New York: Grune & Stratton, 1978.
Dyfyniad MLABerg, Frederick S. Listening and Speech Training Package. Grune & Stratton, 1978.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.