Lambert, D. Smarter Selling: How to grow sales by building trusted relationships (2.). Pearson Education UK.
Chicago-viite (17. p.)Lambert, David;Dugdale. Smarter Selling: How to Grow Sales by Building Trusted Relationships. 2. Pearson Education UK.
MLA-viite (8. p.)Lambert, David;Dugdale. Smarter Selling: How to Grow Sales by Building Trusted Relationships. 2. Pearson Education UK.
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