1. Directorate-General for Energy and Transport, 2007. Innovation and Technological Development in Energy. European Commission, Brussels. 〈http://ec.europa.eu/energy/res/index_en.htm〉 (accessed 28 April 2007).
2. EconStats, 2007. Global Econ Data, World Bank Development Data, IMF International Financial Statistics, IMF World Economic Outlook. 〈http://www.econstats.com/weo/V015.htm〉 (accessed 11 January 2007).
3. EEA, 2006. EU greenhouse gas emissions increase for second year in a row. Press release from the European Environmental Agency, Copenhagen, Denmark. 〈http://www.eea.europa.eu/pressroom/newsreleases/GHG2006-en〉 (accessed 19 September, 2006).
4. Underground storage of carbon dioxide;Holloway,2006
5. IPCC Special Report on Carbon Dioxide Capture and Storage, prepared by Working Group III of the Intergovernmental Panel on Climate Change,2005