1. China yearbook 2012;National Bureau of Statistics of China,2012
2. The 12th five-year plan for energy development;NDRC,2013
3. Energy consumption in the UK overall data tables;The UK Department of Energy & Climate Change,2013
4. United States Energy efficiency report,2011
5. China and a sustainable future: towards a low carbon economy and society, China human development report 2009/10;UNDP,2010