Irving had based his numbers on what purported to be Tagesbefehl 47 ("Daily Order 47", TB 47), a document promulgated by Nazi Propaganda Minister Joseph Goebbels, and on claims made after the war by a former Dresden Nazi functionary, Hans Voigt, without verifying them against official sources available in Dresden. Irving's estimates and sources were first disputed by Walter Weidauer, Mayor of Dresden 1946–1958, in his own account of the Dresden bombing. When it was later confirmed that the TB 47 used was a forgery, Irving published a letter to the editor in The Times on 7 July 1966 retracting his estimates, writing that he had "no interest in promoting or perpetuating false legends". In 1977, the real document TB 47 was located in Dresden by Götz Bergander.
