1. Renewable portfolio standards in the States: balancing goals and implementation strategies;Cory,2007
2. A European strategy for sustainable, competitive and secure energy;Commission of the European Communities,2006
3. Wind energy installed in 2011 totals 41,000 MW;Levesque,2012
4. The energy- and climate goals of the Danish government and results of the energy agreement 2020;Danish Ministry for Climate, Energy and Buildings (Klima,- energi - og bygningsministeriet),2012
5. Wind energy passes 30%;Danish Wind Industry Association,2013