Correspondence with Annie Adama van Scheltema 1946-1954, Friedrich Adler 1948-1958, Julius Braunthal 1954-1964, Paul Hertz 1949-1959, Helmut Hirsch 1961-1965, Benedikt Kautsky 1950-1960 and others; typescripts `August Bebels Briefwechsel mit Friedrich Engels', `Karl Marx in Selbstzeugnissen und Bilddokumenten' and `Kämpfer für die Freiheit' (biographies of 22 Germans); typed copies of correspondence between Adolf Cluss, Friedrich Engels, Karl Marx, Joseph Weydemeyer, Wilhelm Wolff and others, of correspondence between Franz Duncker, Friedrich Engels and Karl Marx and of correspondence between Karl Marx and his family in Holland (Lion Philips and others); file on his and Edmund Silberner's publication concerning life and works of Moses Hess; file on Sonja Kovalevskij; file on the accusations against Herbert Kriedemann, employed by the SPD, of having been an agent of the GESTAPO 1949; issues of the Bulletin der Abteilung für internationale Verbindungen des Petrograder Arbeiter- und Soldaten-Delegierten-Rates (issued in Stockholm) 1917. On the microfilms (list 1-41): diaries 1944-1945 and n.d.; correspondence with Walter Felbel 1947-1950, Heinrich Fröhlich 1949-1950, August Holweg 1949, Hermann Schönleiter 1950, Ernst Schumacher 1949-1950, Willy Wendt 1946-1951; files on the Sozialistische Front: typescript by Blumenberg 'Erfahrungen in der illegalen Arbeit' 1936, documents on legal trials against members of the Sozialistische Front 1936-1942; documents on legal trials and internal purification procedures within the SPD 1945-1951, in particular against Herbert Kriedemann (see also the biographical sketch of the complicated life of Kriedemann by Stefan Appelius) and Walter Spengemann. On the photocopies (list 42-46): typescripts of literary novels by Blumenberg: 'Die Gruppe. Eine Schilderung aus der illegalen Zeit' n.d. and 'Unteroffizier Ernst' n.d.