4WU SX(武淑霞). The spatial and temporal change of nitrogen and phosphorus produced by livestock and poultry & their effects on agricultural non-point pollution in China(我国农村畜禽养殖业氮磷排放变化特征及其对农业面源污染的影响) [D]. Beijing: Chinese Academy of Agricultural Sciences(北京: 中国农业科学院),2005.
5SHEN GX(沈根祥). Research on mechanism and technological conditions of nitrogen-phosphorus wastewater treatment by duckweed(利用浮萍净化氮磷污水机理及其优化工艺条件研究)[D]. Hangzhou: Zhejiang University (杭州: 浙江大学),2005.