Walker, O. C. (2009). Marketing Strategy (5th.). Tata McGraw Hill Education Private Limited.
Chicago-viite (17. p.)Walker, Orville C. Marketing Strategy. 5th. New Delhi: Tata McGraw Hill Education Private Limited, 2009.
MLA-viite (9. p.)Walker, Orville C. Marketing Strategy. 5th. Tata McGraw Hill Education Private Limited, 2009.
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