1. Cenovus, http://www.cenovus.com/operations/technology/co2-enhanced-oil-recovery.html
2. V. Alvarado and E.Manrique, Enhanced Oil Recovery: Field Planning and Development Strategies, Gulf Professional Publishing, Amsterdam, 2010
3. British Petroleum , In Salah Gas, http://www.insalahco2.com/index.php?option=com_content&view=frontpage&Itemid=1&lang=en
4. N. Stern , The Economics of Climate Change: The Stern Review, Cambridge University Press, Cambridge, 2007