Bibliography:

INFORMATION SOURCES

1. Peters, Celeste. The Energy Dilemma. Minnesota: Smart Apple Media, 1980.
2. John H. Gibbons. Energy From Biological Processes, Volume II – Technical and Environmental Analyses. Washington, D.C., U.S. Government Printing Office, 1982.
3. Hayhurst, Chris. Biofuel Power of the Future. New York: The Rosen Publishing Group, Inc., 2003.
4. Snedden, Robert. Energy Alternative. Chicago: Reed Educational & Professional Publishing, 2002.
5. Ellsworth, David and Abeles, Tom. Methane Production For Your Farm. Minnesota: i.e. associates, 1981.
6. Various. “Anaerobic Digest.” Wikipedia. Online. <http://en.wikipedia.org/wiki/Anaerobic_digestion> April 25, 2007.
7. Various. “Biofuel.” Wikipedia. Online. < http://en.wikipedia.org/wiki/Biofuel> April 25, 2007
8. EIA. "Crude Oil and Total Petroleum Imports Top 15 Countries." Energy Information Administration. Online. <http://www.eia.doe.gov/pub/oil_gas/petroleum/data_publications/company_level_imports/current/import.html> April 27th, 2007.

IMAGE SOURCES:

1. static.teriin.org/pub/books/books.htm
2. http://www.ecomagic.org/fruition/leaves-1.jpg
3. http://www.alliantenergy.com/docs/groups/public/documents/pub/p014407.hcsp