Reichheld, F. (2011). The ultimate question 2.0: How net promoter companies thrive in a customer-driven world. Boston, Mass: Harvard Business Press.
Chicago Style aipamenaReichheld, Fred. The Ultimate Question 2.0: How Net Promoter Companies Thrive in a Customer-driven World. Boston, Mass: Harvard Business Press, 2011.
MLA aipamenaReichheld, Fred. The Ultimate Question 2.0: How Net Promoter Companies Thrive in a Customer-driven World. Boston, Mass: Harvard Business Press, 2011.
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