Richardson, L. (2006). The Sales Success Handbook. 20 Lessons to Open and Close Sales Now. McGraw Hill Companies Inc.
Chicago-tyylinen lähdeviittausRichardson, Linda. The Sales Success Handbook. 20 Lessons to Open and Close Sales Now. McGraw Hill Companies Inc, 2006.
MLA-viiteRichardson, Linda. The Sales Success Handbook. 20 Lessons to Open and Close Sales Now. McGraw Hill Companies Inc, 2006.
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