7William E R. Ecological footprints and appropriated carrying capacity: what urban economics leaves out. Environ. Urban, 1992,(4): 121-130.
8Wackenagel M, William E R. Our Ecological Footprint :Reducing Human Impact on the Earth. Gabriola Island, New Society Publishers, 1996.
9Ferng J J. Using composition of land multiplier to estimate ecological footprints associated with production activity. Ecological Economics, 2001, 37.. 159-172.
10Fricker A. The ecological footprint of New Zealand as a step towards sustainability. Futures, 1998, 30(6) : 559-567.