Futrell, C. M. (2014). Fundamentals of Selling customers for life through service. McGraw Hill.
Lua i Stíl Chicago (17ú heag.)Futrell, Charles M. Fundamentals of Selling Customers for Life Through Service. McGraw Hill, 2014.
Lua MLA (8ú heag.)Futrell, Charles M. Fundamentals of Selling Customers for Life Through Service. McGraw Hill, 2014.
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