WALKER, O. E. (1999). Marketing strategy - planning and implementation - Orville C. Walker, Harper W. Boyd, Jean-Claude Larrenche. McGraw Hill.
Chicago-viite (17. p.)WALKER, Orvill E. Marketing Strategy - Planning and Implementation - Orville C. Walker, Harper W. Boyd, Jean-Claude Larrenche. McGraw Hill, 1999.
MLA-viite (8. p.)WALKER, Orvill E. Marketing Strategy - Planning and Implementation - Orville C. Walker, Harper W. Boyd, Jean-Claude Larrenche. McGraw Hill, 1999.
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