1. Motoring Madness
2. US Census Bureau, International Data Base (2005). Available at http://www.census.gov/ipc/www/idbnew.html.
3. S.C. Davis, S.W. Diegel, Transportation Energy Data Book, 24th ed., Oak Ridge National Laboratory Report ORNL-6973, 2004. Available at http://www-cta.ornl.gov.
4. T. Yaegashi, SAE Paper 2004-21-0082, 2004.
5. R.K. Stobart, Fuel Cell Technology for Vehicles 2002–2004, SAE International, 2004.