Kumar, V. (2008). Managing Customers for Profit: Strategies to Increase Profits and Build Loyalty. Pearson Education India Pvt. Ltd.
Chicago-viite (17. p.)Kumar, V. Managing Customers for Profit: Strategies to Increase Profits and Build Loyalty. New Delhi: Pearson Education India Pvt. Ltd, 2008.
MLA-viite (9. p.)Kumar, V. Managing Customers for Profit: Strategies to Increase Profits and Build Loyalty. Pearson Education India Pvt. Ltd, 2008.
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