1. European Commission. Energy for the future, renewable sources of energy—White Paper for a community strategy and action plan. COM(97), 1997, 559 final.
2. EWEA. Prioritising wind energy research: strategic research agenda of the wind energy sector. July 2005.
3. European Commission. Directive on the promotion of electricity produced from renewable energy sources in the internal electricity market. COM(2001/77/EC), 2001.
4. European Commission. Green Paper—towards a European strategy for the security of energy supply. COM (2000), 2000, 769 final.
5. Environmental management: life cycle assessment: principles and framework,1997