Cita APA (7th ed.)
Verderber, R. F. (1982). The challenge of effective speaking (5th ed.). Wadsworth.
Cita Chicago (17th ed.)
Verderber, Rudolph F. The Challenge of Effective Speaking. 5th ed. Califonia: Wadsworth, 1982.
Cita MLA (9th ed.)
Verderber, Rudolph F. The Challenge of Effective Speaking. 5th ed. Wadsworth, 1982.
Atenció: Aquestes cites poden no estar 100% correctes.