Dyfyniad APA

Kotler, P., & Armstrong, G. (1999). Principles of marketing (9 ed.). Prentice Hall.

Dyfyniad Arddull Chicago

Kotler, Philip, and Gray Armstrong. Principles of Marketing. 9 ed. London ; New York: Prentice Hall, 1999.

Dyfyniad MLA

Kotler, Philip, and Gray Armstrong. Principles of Marketing. 9 ed. Prentice Hall, 1999.

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