Ho Khanh Lam, Nguyen Xuan Truong, and Le Thi Hue. “ ANALYSIS PERFORMANCE OF INTERNET WEB CACHING ARCHITECTURE BASE ON USING MULTICLASS CLOSED PRODUCT FORM QUEUING NETWORK (MCPFQN)”. UTEHY Journal of Applied Science and Technology, Vol. 13, Apr. 2017, pp. 63-68, http://tapchi.utehy.edu.vn/index.php/jst/article/view/215.