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[2] (4/15/2010). Using Biochemical Methane Potentials & Anaerobic Toxicity Assay. Available: http://www.epa.gov/agstar/documents/conf10/Moody_Final.pdf.

[3] (March 14,2008). How to Build a Backyard Biogas Plant. Available: http://www.greenoptimistic.com/2008/03/14/how-to-build-a-backyard-biogas-plant/#.VF0E5PnF98E.

[4] W. Telliard, "Total, fixed, volatile solids in water, solids, and biosolids," EPA, Tech. Rep. EPA-821-R-01-015, 2001.