Dyfyniad APA

Etzel, M. J., & Walker, B. J. S. (2001). Marketing (12th ed.). McGraw-Hill.

Dyfyniad Arddull Chicago

Etzel, Michael J., and Bruce J. Stanton Walker. Marketing. 12th ed. Boston: McGraw-Hill, 2001.

Dyfyniad MLA

Etzel, Michael J., and Bruce J. Stanton Walker. Marketing. 12th ed. McGraw-Hill, 2001.

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