H Wien Nie; Vu Thi Hao; Tran Thi Hoai; Mai Gia Thao; Bui Cong Gia Bao; Nguyen Khac Manh; Thai Tien Dung. Determination of Total Nitrogen and Phosphorus in Soil by Ion Chromatography With Conductivity Detector Following Persulfate Digestion Method. JMST 2022, 272-278.