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http://ww2.nscc.edu/gerth_d/MKT2220000/Lecture_Notes/unit11.htm
Note: The above lecture notes were compiled by David Gerth. These materials are a composite of quotations, paraphrases, and ideas from Marketing: Real People, Real Choices, Solomon & Stuart, 2003, Prentice Hall; Contemporary Marketing, Boone & Kurtz, 2004, Thomson; Principles of Marketing, Kotler & Armstrong, 2004, Prentice Hall; Consumer Behavior, Schiffman & Kanuk, 2004, Prentice Hall; and David Gerth. They are only intended for the noncommercial use of students in David Gerth’s marketing classes for educational purposes.