Dyfyniad APA

Kotler, P. (1989). Principles of marketing (3rd.). Prentice Hall.

Dyfyniad Arddull Chicago

Kotler, Philip. Principles of Marketing. 3rd. New Delhi: Prentice Hall, 1989.

Dyfyniad MLA

Kotler, Philip. Principles of Marketing. 3rd. Prentice Hall, 1989.

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