Song Giang, Le, Dau Van Ngo, and Nguyen Cuu Tue. “AN OPTIMIZATION PROBLEM FOR RIVER WATER QUALITY CONTROL”. Science and Technology Development Journal 6, no. 11 (November 30, 2003): 21-26. Accessed May 19, 2024. http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/3372.