1. Vogel, J.U.S. DOE Hydrogen Program 2008 Annual Progress Report._nolinebreak/_nolinebreakhttp://www.hydrogen.energy.gov/pdfs/progress08/v_d_4_vogel.pdf.
2. Transportation Energy Data Book,27th ed.; ORNL-6981;Oak Ridge National Laboratory:Oak Ridge, TN,2008; pp1−16.
3. Learning Demonstration Vehicle Greenhouse Gas Emissions.http://www.nrel.gov/hydrogen/docs/cdp/cdp_62.ppt#494,1,CDP#62.
4. Multi-Year Research, Development and Demonstration Plan, Hydrogen, Fuel Cells & Infrastructure Technologies Program, October2007, Table 3.4.2.
5. Hydrogen and Fuel Cell Technical Advisory Committee to the Department of Energy, Hydrogen and Fuel Cell Technical Advisory Committee Biennial Report to the Secretary of Energy (September 2007), retrieved August 27,2008, fromhttp://www.hydrogen.energy.gov/pdfs/htac_letter_report_attach.pdf.