Kotler, P., & Armstrong, G. (1999). Principles of marketing (8th ed.). Prentice Hall.
Dyfyniad Arddull ChicagoKotler, Philip, and Gary Armstrong. Principles of Marketing. 8th ed. Upper Saddle River, NJ ; New Delhi: Prentice Hall, 1999.
Dyfyniad MLAKotler, Philip, and Gary Armstrong. Principles of Marketing. 8th ed. Prentice Hall, 1999.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.