Lucas, Robert W.
Customer service : skills for success
McGrow-Hill, 2015
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Knapp, Donna
A guide to Service desk concepts / Donna Knapp
Course Tecnology Cengage, 2014
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Loughary, John W.
Helping others help themselves a guide to connseling skills
McGraw-Hill, 1979
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Lucas, Robert W.
Customer service : building successful skills for the twenty-first century
McGraw-Hill, 2005
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Francis Peter S.J.
Soft skills and professional communication
Tata McGraw-Hill, 2012
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