Chen, You-Hua, and Xiao-Wei Wen. “Vertical Cooperative Advertising With Substitute Brands: Brief Overview”. Recent Studies in Mathematics and Computer Science Vol. 1 (March 27, 2020): 75-88. Accessed June 19, 2026. https://stm1.bookpi.org/index.php/rsmcs-v1/article/view/1136.