1. Cai, W., 1994. The matter-element model and its application, Scientific and Technical Documentation Press, Beijing (in Chinese).
2. Developing an ecosystem-based capability for ecological risk assessments;Cairns;Environ. Prof.,1992
3. A proposed framework for developing indicators of ecosystem health;Cairns;Hydrobiologia,1993
4. The value of the world's ecosystem services and natural capital;Costanza;Nature,1997
5. Entropy-based urban ecological security assessment: taking Pingdingshan City as an example;Dong;J. Northwest Normal Univ.,2011