List of sources:
Baumann, G. Early survey in the Orange Free State. South African Survey Journal, 1925, Vol. 1, pp. 309-312.
Baumann, G. & Bright, E. The lost republic: The biography of a land-surveyor. London: Faber & Faber, 1940.
Coetzer, A.C.M. Geskiedenis van die Nasionale Museum, 1877-1911. Navorsinge van die Nasionale Museum, 1989, Vol. 6, No. 8, pp.243-291.
Dictionary of South African biography, Vol. 4, 1981.
JewishGen. Kehila Links. The Baumann family. Retrieved on 23 March 2023 from https://kehilalinks.jewishgen.org/bloemfontein/Baumann.html
Liebenberg, E.C. Die topografiese kartering van Suid-Afrika, 1879-1972, 'n histories-geografiese ontleding (p. 139, 419, 422). MA-verhandeling in Geografie, Universiteit van Suid-Afrika, 1973.
National Automated Archival Information Retrieval System (NAAIRS). http://www.national.archives.gov.za/naairs.htm Documents relating to Gustav Baumann / G. Baumann.
Obituary. South African Survey Journal, 1930, Vol. 7, pp. 269-274.
Ritchie, W. The history of the South African College, 1829-1918 (Vol. 2, list of alumni). Cape Town: T. Maskew Miller, 1918.
South African Association for the Advancement of Science. Report, 1910, list of members.
South African Survey Journal, 1924-1927, Vol. 1-2, The Institutes of Land Surveyors.
Standard encyclopaedia of southern Africa (SESA). Cape Town: NASOU, 1970-1976.
University of the Cape of Good Hope. Calendar, 1884-1885.