Nguyen Trung Hiep, Le Thi Hong Tuyet, Dinh Thi Nga, and Phan Dinh Tuan. “A Research on the Performance of down-Flow Hanging Sponge (DHS) Reactor Treating Domestic Wastewater”. <i>Vietnam Journal of Science and Technology</i> 56, no. 4 (August 6, 2018): 482–492. Accessed March 19, 2026. https://cip.vast.vn/jst/article/view/10878.