1. Junan Xie, Dongheng Hao and Wen Xie. Contemporary economic management, Vol30 (2008), P. 1-7(in Chinese).
2. Leqin Jin and Rui Liu. Economic Issues Explore, Vol1 (2009), P. 84-87(in Chinese).
3. Yuan Zhou and Pan Peng. Journal of Theory, Vol4 (2010), P. 39-42(in Chinese).
4. Shengyun Wang and Ruifang Zhang. Reform and opening, Vol10 (2011), P. 31-33(in Chinese).
5. Zhenhai Ji. Journal of Environmental Management Cadre College, Vol18 (2008), P. 1-4(in Chinese).