Cita APA (7th ed.)
Verderber, R. F. (1976). The challenge of effective speaking (3rd ed.). Wadsworth.
Cita Chicago (17th ed.)
Verderber, Rudolph F. The Challenge of Effective Speaking. 3rd ed. Califonia: Wadsworth, 1976.
Cita MLA (9th ed.)
Verderber, Rudolph F. The Challenge of Effective Speaking. 3rd ed. Wadsworth, 1976.
Atenció: Aquestes cites poden no estar 100% correctes.