Wang, Lai Wang, and Thanh Tuyen Tran. “Vietnamese Milk Industry Forecasting: A Grey System Theory Case of Vinamilk”. International Journal of Asian Social Science 4, no. 6 (June 16, 2014): 779–790. Accessed May 15, 2025. https://www.archive.aessweb.com/index.php/5007/article/view/2677.