1. Ando, H., 2005. Japan's challenge towards fuel cell and hydrogen society—national strategy and business chance, presentation at the First International Fuel Cell Expo, Tokyo, Japan, January 19–21.
2. Birky, A., Greene, D., Gross, T. et al., 2001. Future US Highway Energy Use: a Fifty year Perspective, Fig. 3, p. 3.
3. Bush, G.W., 2003. State of the Union 2003, available online at: 〈http://www.whitehouse.gov/news/releases/2003/01/20030128-19.html〉.
4. Chen, Q., Liu, S., Feng, F., et al., 2004. The Coming of Auto Age in China. Development Press of China, Beijing, pp. 49–50.
5. Davis, S.C., Diegel, S.W., 2006a. Transportation Energy Data Book: edition 25. Table 3.1 and Table 3.2. Available online at: cta.ornl.gov/data