APA (7th ed.) Zitazioa
Hayes, B. E. (2009). Beyond the ultimate question: A systematic approach to improve customer loyalty. ASQ Quality Press.
Chicago Style (17th ed.) Zitazioa
Hayes, Bob E. Beyond the Ultimate Question: A Systematic Approach to Improve Customer Loyalty. Milwaukee, Wisconsin: ASQ Quality Press, 2009.
MLA (9th ed.) Zitazioa
Hayes, Bob E. Beyond the Ultimate Question: A Systematic Approach to Improve Customer Loyalty. ASQ Quality Press, 2009.
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