Rosenthal, Elisabeth (2008-02-08). "Biofuels Deemed a Greenhouse Threat". New York Times. Archived from the original on 2019-08-07. Retrieved 2017-02-23. Registration required. "Almost all biofuels used today cause more greenhouse gas emissions than conventional fuels if the full emissions costs of producing these “green” fuels are taken into account, two studies being published Thursday have concluded."
Smil, p. 204 * Tester, et al., p. 303 * "OPEC 2005 Annual Statistical Bulletin"(PDF). Organization of Petroleum Exporting Countries (OPEC). 2005. Archived from the original(PDF) on 2007-01-31. Retrieved 2007-01-25.
Smil, p. 204 * Tester, et al., p. 303 * "OPEC 2005 Annual Statistical Bulletin"(PDF). Organization of Petroleum Exporting Countries (OPEC). 2005. Archived from the original(PDF) on 2007-01-31. Retrieved 2007-01-25.
Rosenthal, Elisabeth (2008-02-08). "Biofuels Deemed a Greenhouse Threat". New York Times. Archived from the original on 2019-08-07. Retrieved 2017-02-23. Registration required. "Almost all biofuels used today cause more greenhouse gas emissions than conventional fuels if the full emissions costs of producing these “green” fuels are taken into account, two studies being published Thursday have concluded."