Kumar, V. (2013). Profitable Customer Engagement: Concepts, Metrics, and Strategies. SAGE Publications India Pvt. Ltd.
Chicago-viite (17. p.)Kumar, V. Profitable Customer Engagement: Concepts, Metrics, and Strategies. New Delhi: SAGE Publications India Pvt. Ltd, 2013.
MLA-viite (9. p.)Kumar, V. Profitable Customer Engagement: Concepts, Metrics, and Strategies. SAGE Publications India Pvt. Ltd, 2013.
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