@article{liang2012comparing,
  title = {Comparing urban solid waste recycling from the viewpoint of urban metabolism based on physical input–output model: A case of Suzhou in China}
  author = {Liang, Sai; Zhang, Tianzhu},
  journal = {Waste Management},
  url = {http://www.sciencedirect.com/science/article/pii/S0956053X11003795},
  doi = {10.1016/j.wasman.2011.08.018},
  year = {2012}
}