1. Nielsen PH and Wenzel H, Environmental assessment of ethanol produced from corn starch and used as an alternative to conventional gasoline for car driving. The Institute for Product Development Technical University of Denmark (2005). Available at: www.ipu.dk/upload/publikationer/bio-ethanol-report.pdf [May 2009].
2. Ethanol production using corn, switchgrass, and wood; biodiesel production using soybean and sunflower.;Pimentel;Natural Resources Research,2005
3. Estimating the net energy balance of corn ethanol.;Shapouri;Agricultural Economic Report,1995
4. The energy balance of corn ethanol: An update.;Shapouri;Agricultural Economic Report,2002
5. A comprehensive energy and economic assessment of biofuels: When green is not enough.;Ulgiati;Crit Rev Plant Sci,2001