List of sources:
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Cape of Good Hope. Report of the Trustees of the South African Museum, 1897.
Cape of Good Hope. Report of the Surveyor-General, 1895, 1897.
Chemical and Metallurgical Society of South Africa. Proceedings, 1899, Vol. 2, list of members and associates.
Dictionary of South African biography, Vol. 3, 1977.
Hall, A.L. A bibliography of South African geology to the end of 1920. Pretoria: Geological Survey, Memoir No. 18, 1922.
Hugo, P.J., Schalk, K.E.L. & Barnes, S.J. Bibliography of South West African / Namibian earth science. Windhoek: Geological Survey, 1983.
Ritchie, W. The history of the South African College, 1829-1918. Cape Town: T. Maskew Miller, 1918.
Rose, J.G. Paul Daniel Hahn: First memorial lecture. South African Industrial Chemist, November 1960, Vol. 14, pp. 204-206.
South African Association for the Advancement of Science. Report, 1910, 1911, 1914, 1915.
South African bibliography to the year 1925. London: Mansell, 1979.
South African who's who, 1908.
Union of South Africa. Public service list, 1914.
University of the Cape of Good Hope. Calendar, 1893/4, 1903/4, 1915/6.