King, G. Secrets of Selling: How to win in any sales situation (2.). Pearson Education UK.
Chicago-viite (17. p.)King, Geoff. Secrets of Selling: How to Win in Any Sales Situation. 2. Pearson Education UK.
MLA-viite (8. p.)King, Geoff. Secrets of Selling: How to Win in Any Sales Situation. 2. Pearson Education UK.
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