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2. BP Energy Outlook 2030 (BP, 2013).
3. Hughes, J. D. Drill, Baby, Drill (Post Carbon Institute, 2013).
4. US Geological Survey. Open-File Report 2012–1118 (USGS, 2012).
5. Jacoby, H. D. et al. Econ. Energy Environ. Policy 1, 37–51 (2012).