Carnegie, Dorothy
      
      
         Dale Carnegie and Associates, 1962
       Buku Teks
   
Zarefsky, David
      
      
         Allyn and Bacon, 2011
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Zarefsky, David
      
      
         Allyn and Bacon, 1996
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Chan, Janis Fisher
      
      
         [American Management Association;, ], 1999
       eBooks
   
Turner, Stuart
      
      
         Mc Graw Hill, 1991
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