1. The Changing Wealth of Nations (World Bank, 2011).
2. NCC The State of Natural Capital. (Department for Environment Food and Rural Affairs, 2014).
3. Energy and Carbon — Managing the Risks (ExxonMobil, 2014).
4. Crooks, E. Exxon warns global warming targets 'unlikely' to be met. Financial Times (31 March 2014).
5. World Development Indicators (The World Bank, 2012).