Kleppner, O., & Govoni, N. A. P. (1980). Advertising procedure (7th ed.). Prentice-Hall.
Cita Chicago (17th ed.)Kleppner, Otto, i Norman A. P. Govoni. Advertising Procedure. 7th ed. Englewood Cliffs, N.J: Prentice-Hall, 1980.
Cita MLA (9th ed.)Kleppner, Otto, i Norman A. P. Govoni. Advertising Procedure. 7th ed. Prentice-Hall, 1980.
Atenció: Aquestes cites poden no estar 100% correctes.