Tsao, Y.-C., V. T. Linh, and T.-H. Chen. “DUOPOLY MARKET COMPETITION OF PRICING AND SERVICE POLICIES UNDER A DUAL-SALE CHANNEL”. International Journal of Industrial Engineering: Theory, Applications and Practice, vol. 29, no. 2, Apr. 2022, doi:10.23055/ijietap.2022.29.2.7693.