^Gaudi, Robert. African Kaiser: General Paul von Lettow-Vorbeck and the Great War in Africa, 1914-1918. New York. 2017. ISBN 978-0-425-28371-4. OCLC 946903000.
^Gewald, Jan-Bart, Herero Heroes: A Socio-political History of the Herero of Namibia, 1890-1923, London: James Curry Ltd (1999), ISBN0852557493, p. 156
