1. Bauquis, P.R., 2006. What future for hydrocarbons with the incoming peaks of oil and gas? 〈http://www.aspoitalia.net/images/stories/aspo5presentations/Bauquis_ASPO5.pdf〉.
2. BP, 2007. Statistical Review of World Energy, 2007 edition 〈http://www.bp.com〉.
3. Campbell, C.J., 1999. The imminent peak of world oil production. Presentation to a House of Commons All-Party Committee on 7th July 1999 〈http://www.hubbertpeak.com/campbell/commons.htm〉.
4. Campbell, C., Laherrere, J., 1998. The end of cheap oil. Scientific American, March 1998 〈www.wolf.readinglitho.co.uk/subpages/sciam/End%20of%20Cheap%20Oil.html〉.
5. Caruso, G., 2005. EIA, when will world oil production peak? 〈http://www.eia.doe.gov/neic/speeches/Caruso061305.pdf〉.