1. Aniti, L., 2004. Electricity prices. In: Annual Energy Outlook 2004 with Projections to 2025. National Energy Information Center, Washington, DC, p. 278. .
2. Conner, M., 2005. 5.13c Estimated petroleum consumption: transportation sector and end-use total, 1949–2004. Annual Energy Review (AER). Energy Information Administration, Washington, DC, p. 435.
3. Hydrogen: its technology and implications;Cox,1977
4. Geffen, C., 2003. PNNL global energy technology strategy project (GTSP): research programs – MiniCAM vol. 2006. .
5. Ivy, J., 2004. Summary of electrolytic hydrogen production: milestone completion report. NREL, Golden, CO. NREL/MP-560-35948.