9Jim Cook,Jan Beyea.??Bioenergy in the United States: progress and possibilities 1 1 Based on the final report for NREL Subcontract No. ACD-5-15212-01 with the National Audubon Society.(J)Biomass and Bioenergy . 2000 (6)
10Robert Gross,Matthew Leach,Ausilio Bauen.??Progress in renewable energy(J)Environment International . 2002 (1)