Dyfyniad APA

Verderber, R. (2008). The challenge of effective speaking (Fourteenth edition.). Belmont, CA: Cengage Learning.

Dyfyniad Arddull Chicago

Verderber, Rudolph. The Challenge of Effective Speaking. Fourteenth edition. Belmont, CA: Cengage Learning, 2008.

Dyfyniad MLA

Verderber, Rudolph. The Challenge of Effective Speaking. Fourteenth edition. Belmont, CA: Cengage Learning, 2008.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.