Collier, M. (2011). The ultimate online-customer service guide: How to connect with your customer to all more. Wiley.
Chicago-viite (17. p.)Collier, Marsha. The Ultimate Online-customer Service Guide: How to Connect with Your Customer to All More. Hoboken, N.J: Wiley, 2011.
MLA-viite (9. p.)Collier, Marsha. The Ultimate Online-customer Service Guide: How to Connect with Your Customer to All More. Wiley, 2011.
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