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2. BP p.l.c BP Statistical Review of World Energy 2012
3. The economic impact of shale gas extraction: A review of existing studies;Kinnaman;Ecol Econ.,2011
4. Continental Economics, Inc. The Economic Impacts of US Shale Gas Production on Ohio Consumers 2012 http://www.eidohio.org/wp-content/uploads/2012/02/Economic-Impacts-of-Shale-Gas-Production_Final_23-Jan-2012.pdf
5. EIA United States shale gas maps 2011 http://www.eia.gov/pub/oil_gas/natural_gas/analysis_publications/maps/maps.htm