Marks, R. B. (1991). Personal selling: An interactive approach (4th ed.). Allyn and Bacon.
Chicago-viite (17. p.)Marks, Ronald B. Personal Selling: An Interactive Approach. 4th ed. Boston: Allyn and Bacon, 1991.
MLA-viite (9. p.)Marks, Ronald B. Personal Selling: An Interactive Approach. 4th ed. Allyn and Bacon, 1991.
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