Bird, D. (2008). Commonsense direct and digital marketing (5th ed.). Kogan Page.
Dyfyniad Arddull ChicagoBird, Drayton. Commonsense Direct and Digital Marketing. 5th ed. New Delhi: Kogan Page, 2008.
Dyfyniad MLABird, Drayton. Commonsense Direct and Digital Marketing. 5th ed. Kogan Page, 2008.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.