Sources on the development of the Socialist International (1907 - 1919) speech at the XXXVII IALHI Conference, Zurich, 6-9 September 2006 - Callesen, Gerd 1940- (FES Library, 2006)
Electronic ed.: Bonn : FES Library, 2006. - Gedruckte Version des Textes auch erschienen in: Annual IALHI conference, 2006, S. 14 - 18