Cowell, D. W. (1993). Services marketing (3rd ed.). Butterworth-Heinemann.
Chicago Style (17. basım) AtıfCowell, Donald W. Services Marketing. 3rd ed. Oxford: Butterworth-Heinemann, 1993.
MLA (9th ed.) AtıfCowell, Donald W. Services Marketing. 3rd ed. Butterworth-Heinemann, 1993.
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