Hirsch, Robert L.; Bezdek, Roger; Wendling, Robert (February 2005). "Peaking Of World Oil Production: Impacts, Mitigation, & Risk Management"(PDF). Science Applications International Corporation, U.S. Department of Energy, National Energy Technology Laboratory. Archived from the original(PDF) on 15 December 2009. Retrieved 28 November 2009.
Hirsch, Robert L. (February 2007). "Peaking of World Oil Production: Recent Forecasts"(PDF). Science Applications International Corporation, U.S. Department of Energy, National Energy Technology Laboratory. Archived from the original(PDF) on 19 February 2015. Retrieved 19 February 2015.
Hirsch, Robert L.; Bezdek, Roger; Wendling, Robert (February 2005). "Peaking Of World Oil Production: Impacts, Mitigation, & Risk Management"(PDF). Science Applications International Corporation, U.S. Department of Energy, National Energy Technology Laboratory. Archived from the original(PDF) on 15 December 2009. Retrieved 28 November 2009.
Hirsch, Robert L. (February 2007). "Peaking of World Oil Production: Recent Forecasts"(PDF). Science Applications International Corporation, U.S. Department of Energy, National Energy Technology Laboratory. Archived from the original(PDF) on 19 February 2015. Retrieved 19 February 2015.