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Cape of Good Hope. Civil service list, 1901, 1902.
Cape of Good Hope. Report of the Government Electrical Engineer, 1899.
Draper, J.R. The engineer's contribution: A history of the South African Institution of Mechanical Engineers, 1892-1967 (p. 245). Johannesburg: SAIME, 1967.
General directory of South Africa (Cape Town), 1903.
George Muirhead Clark. In Graceâ€™s Guide to British Industrial History. http://www.gracesguide.co.uk/George_Muirhead_Clark
National Automated Archival Information Retrieval System (NAAIRS). http://www.national.archives.gov.za/naairs.htm Documents relating to Clark, G.M.
Royal Society of London. Catalogue of scientific papers [1800-1900]. London: Royal Society, 1867-1925.
Royal Society of South Africa. Transactions, 1908-1910, Vol. 1 and 1917, Vol. 6: Lists of members.
South African Association for the Advancement of Science. Report, 1918, list of members.
South African bibliography to the year 1925. London: Mansell, 1979.
South African Geographical Journal, 1917, Vol. 1(1), list of members.
South African Philosophical Society. Transactions, 1900-1907, Vol. 11, 16 and 17: Lists of members.