6Junguo Liu,H G Savenije,Jianxin Xu.Forecast of Water Demand in WeinanCity in China Using WDF—ANN model[J].Physics and Chemistry of theEarth,2003(28):219-224.
7CHEN J S,GAO X M,HE D W,et al.Nitrogen Contamination in the Yan-gtze River System,China[J].Journal of Hazardous Materials,2000,73(2):107-113.