Dyfyniad APA

Kleppner, O., & Govoni, N. A. P. (1980). Advertising procedure (7th ed.). Prentice-Hall.

Dyfyniad Arddull Chicago

Kleppner, Otto, and Norman A. P. Govoni. Advertising Procedure. 7th ed. Englewood Cliffs, N.J: Prentice-Hall, 1980.

Dyfyniad MLA

Kleppner, Otto, and Norman A. P. Govoni. Advertising Procedure. 7th ed. Prentice-Hall, 1980.

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