Citazione Stile APA (7a Edizione)

Verderber, R. F. (1991). The challenge of effective speaking (8th ed.). Wadsworth Pub. Co..

Citazione stile Chigago Style (17a edizione)

Verderber, Rudolph F. The Challenge of Effective Speaking. 8th ed. Belmont, Calif.: Wadsworth Pub. Co., 1991.

Citatione MLA (9a ed.)

Verderber, Rudolph F. The Challenge of Effective Speaking. 8th ed. Wadsworth Pub. Co., 1991.