Karr, R., & Blohowiak, D. (1998). Complete idiot's guide to great customer service (1st.). Prentice-Hall..
Chicago Style aipamenaKarr, Ron, and Don Blohowiak. Complete Idiot's Guide to Great Customer Service. 1st. N,Delhi: Prentice-Hall., 1998.
MLA aipamenaKarr, Ron, and Don Blohowiak. Complete Idiot's Guide to Great Customer Service. 1st. Prentice-Hall., 1998.
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