1. EU Energy and Transport in Figures, Statistical Pocket Book 2007/2008,2008
2. Climate Change 2001: Mitigation,2001
3. Summary of the Impact Assessment,2008
4. http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=COM:2007:0723:FIN:EN:PDF
5. Towards a Sustainable Northern European Housing Stock: Figures, Facts and Future;Itard,2009