info:oai:pure.iiasa.ac.at:13769info:ofi/fmt:xml:xsd:journalZhangY.Zhang, Y.LuH.Lu, H.FathB.Fath, B.ZhengH.Zheng, H.SunX.Sun, X.LiY.Li, Y.1650August 20161520-5851A Network Flow Analysis of the Nitrogen Metabolism in Beijing, ChinaEnvironmental Science & Technology8558-8567article