* [https://www.theguardian.com/commentisfree/2007/feb/07/globalwarmingdeniers The dire global cooling problem], Bradford Plumer ,the guardian, 7 Feb 2007 | * [https://www.theguardian.com/commentisfree/2007/feb/07/globalwarmingdeniers The dire global cooling problem], Bradford Plumer ,the guardian, 7 Feb 2007 |