Kotler, P., & Armstrong, G. (1999). Principles of marketing (9 ed.). Prentice Hall.
Citazione stile Chigago Style (17a edizione)Kotler, Philip, e Gray Armstrong. Principles of Marketing. 9 ed. London ; New York: Prentice Hall, 1999.
Citatione MLA (9a ed.)Kotler, Philip, e Gray Armstrong. Principles of Marketing. 9 ed. Prentice Hall, 1999.