He first wrote on the matter in the September 13, 2001, edition of the online magazine Telepolis[1] and has subsequently published two books on 9/11: Verschwörungen, Verschwörungstheorien und die Geheimnisse des 11.9 was, under the title 'Conspiracies, Conspiracy Theories and the Secrets of 9/11, the only book promoting a 9/11 conspiracy theories to be translated into English from German.[citation needed] Its sequel was entitled Fakten, Fälschungen und die unterdrückten Beweise des 11.9, (Facts, Forgeries and the Suppressed Evidence of 9/11).