Nguyen Thi Nguyet, Tran Thi Trang, Nguyen Trong Nghia, Nguyen Thi Chuc, and Dao Thi Nga. “RESEARCH FABRICATION AND APPLICATION OF MnO2 FOR WATER TREATMENT”. UTEHY Journal of Applied Science and Technology, Vol. 9, Apr. 2020, pp. 82-85, http://jst.utehy.edu.vn/index.php/jst/article/view/307.