San, N. E. E. and Aryupong , M. (2020) “Effects of Sales Promotional Tools on Product Quality, Brand Image, and Customer Satisfaction: The Application of Inverted U-Shaped Theory”, Business Administration and Management Journal Review, 12(1), pp. 84–103. available at: https://so01.tci-thaijo.org/index.php/bahcuojs/article/view/176208 (accessed: 28 August 2026).