1. International Press Correspondence(Inprecorr) (1929) Vienna: Inprecorr.
2. Russian State Archive for Social and Political History (RGASPI) Moscow.
3. Stiftung Archiv der Parteien und Massenorganisationen der DDR Zentrales Parteiarchiv im Bundesarchiv-Lichterfelde (SAPMO BA-ZPA) Berlin.
4. From Cameroon to Germany and Back via Moscow and Paris: The Political Career of Joseph Bilé (1892—1959), Performer, “Negerarbeiter” and Comintern Activist