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2. U.S. Energy Information Administration. Monthly Energy Review – August 2012; DOE/EIA-0035, August 2012; available from:http://www.eia.gov/todayinenergy/detail.cfm?id=7350.
3. Implications of the Recent Reductions in Natural Gas Prices for Emissions of CO2 from the US Power Sector
4. Today in Energy.Monthly Energy Review;U.S. Energy Information Administration:Washington, DC, July 27, 2012; available from:http://www.eia.gov/todayinenergy/detail.cfm?id=7290.
5. U.S. Energy Information Administration, Annual Energy Outlook 2012; DOE/EIA-0383, June 2012; available from:http://www.eia.gov/forecasts/aeo/pdf/0383(2012).pdf.