Davidow, W. . H. (1989). Total customer service: The ultimate weapon. New York: Harper Perennial.
Chicago Style aipamenaDavidow, William H. Total Customer Service: The Ultimate Weapon. New York: Harper Perennial, 1989.
MLA aipamenaDavidow, William H. Total Customer Service: The Ultimate Weapon. New York: Harper Perennial, 1989.
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