"Summary for Policymakers"(PDF). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change. 5 February 2007. Archived from the original(PDF) on 3 February 2007. Retrieved 2 February 2007.
"Summary for Policymakers"(PDF). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change. 5 February 2007. Archived from the original(PDF) on 3 February 2007. Retrieved 2 February 2007.