Kotler, P., & Gray Armstrong. (1992). Principles of marketing (5th ed.). Prentice-Hall.
Chicago Style aipamenaKotler, Philip, and Gray Armstrong. Principles of Marketing. 5th ed. New Delhi: Prentice-Hall, 1992.
MLA aipamenaKotler, Philip, and Gray Armstrong. Principles of Marketing. 5th ed. Prentice-Hall, 1992.
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