San Ha, Phan, Le Son, and Nguyen An. “CLASSIFICATION OF CLAY SOILS BY USING METHYLENE BLUE ADSORPTION TEST”. Science and Technology Development Journal 10, no. 7 (July 31, 2007): 63-74. Accessed May 18, 2024. http://stdj.scienceandtechnology.com.vn/index.php/stdj/article/view/2806.