1. Renewables global futures report;REN21,2013
2. Renewable energy now cheaper than new fossil fuels in Australia;Bloomberg New Energy Finance,2013
3. Energieziel 2050: 100% Strom aus erneuerbaren Quellen;Klaus,2010
4. Results and challenges 2010;Danish Energy Regulatory Authority,2011
5. 2050 pathways analysis, UK;Department of Energy and Climate Change,2010