1. Opportunities and barriers to pumped-hydro energy storage in the United States;Yang;Renew Sustain Energy Rev,2011
2. UN (United Nations), Kyoto Protocol to the United Nations Framework Convention on Climate Change, 1998. Available from: 〈http://unfccc.int/resource/docs/convkp/kpeng.pdf〉 [accessed 26.03.14].
3. EC (European Commission), Directive 2009/28/EC of the European Parliament and of the Council of 23 April 2009 on the promotion of the use of energy from renewable sources and amending and subsequently repealing Directives 2001/77/EC and 2003/30/EC. Available from: 〈http://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32009L0028&rid=1〉 [accessed 04.07.14].
4. Global potential for wind-generated electricity;Lu;Proc Natl Acad Sci USA,2009
5. Taulan JP, Laurier P, Bourrilhon M,Bornard L. Pump-turbine integration in renewable energy systems. In: Proceedings of the 2009 waterpower XVI.