1. LI Kai-xin. Journal of Jiamusi University(Natural Science Edition), Vol. 21, 141~144 (2003).
2. LIN Kai-rong. Journal of Shandong Institute of Light Industry(Natural Science Edition) , Vol. 22(1), 95~98(2008).
3. Bächle, Michael. IEEE Software, v 24, n 6: 105-108, November/December (2007).
4. China Business Report. 2009 ~ 2012 China's investment strategy of the car rental industry report reference, (2009, 5).
5. SONG Dan, ZHAO Kun. Journal of Guizhou University of Technology(Social Science Edition) , Vol. 9(5): 116~118(2007).