8Ulrika Geber, Johanna Bjorklund. The relationship between ecosystem services and purchased input in Swedish wastewater treatment systems - a case study [J]. Ecological Engineering, 2002, 19(1): 97-117.
9M. Nelson, H. T. Odum, M. T. Brown, et al. "Living off the land": resource efficiency of wetland wastewater treatment [J].Advances in Space Research, 2001,27(9): 1547-1556.
10A.S. Juwarkar, B. Oke, A. Juwarkar, et al. Domestic wastewater treatment through constructed wetland in India[J]. Water Science and Technology, 1995, 32(3) : 291-294.