Payne, S. (1997). Delivering customer service: How to win a competitive edge through managing customer. Grolier.
Lua i Stíl Chicago (17ú heag.)Payne, Shelia. Delivering Customer Service: How to Win a Competitive Edge Through Managing Customer. Wanchai, Hong Kong: Grolier, 1997.
Lua MLA (9ú heag.)Payne, Shelia. Delivering Customer Service: How to Win a Competitive Edge Through Managing Customer. Grolier, 1997.
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