1. U.S. Energy Information Administration, U.S. Department of Energy (2012) International Energy Statistics, U.S. Energy Information Administration (http://www.eia.gov/cfapps/ipdbproject/IEDIndex3.cfm)
2. BP Global (2011) BP Energy Outlook 2030, BP Global
3. Tropical forests and climate policy;Gullison;Science,2007
4. Global economic activity and crude oil prices: a cointegration analysis;He;Energy Econ.,2010
5. Production of liquid biofuels from renewable resources;Nigam;Prog. Energy Combust. Sci.,2011