Cummins, J. (1991). Sales promotion: How to create and implement campaigns that really work. Universal book stall.
Chicago Style aipamenaCummins, Julian. Sales Promotion: How to Create and Implement Campaigns That Really Work. New Delhi: Universal book stall, 1991.
MLA aipamenaCummins, Julian. Sales Promotion: How to Create and Implement Campaigns That Really Work. Universal book stall, 1991.
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