1. Oil scarcity, energy and long-term oil prices—lessons learned (and unlearned);Lynch;IAEE Newsletter,1999
2. An assessment of world hydrocarbon resources;Rogner;Annual Review of Energy,1997
3. US Office of Transportation Technologies, Fact of the Week Archives, Fact #85, April 20, 1999, www.ott.doe.gov/facts/archives/fotw85.htm.
4. Alternative transportation fuels: a comparative analysis, report by AICHE Government Relations Committee, Sept 1997.
5. U.S. consumption of alternative road fuels growing;Oil and Gas Journal,1999