Kotler, P. (1991). Principles of marketing (5th ed.). Prentice-Hall.
Cita Chicago (17th ed.)Kotler, Philip. Principles of Marketing. 5th ed. New Delhi: Prentice-Hall, 1991.
Cita MLA (9th ed.)Kotler, Philip. Principles of Marketing. 5th ed. Prentice-Hall, 1991.
Atenció: Aquestes cites poden no estar 100% correctes.