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Biographical Dictionary of People in Engineering. Webb, Harry Howard. Retrieved on 26 April 2021 from https://books.google.co.za/books?id=l2492-xSSNoC&pg=PA225&lpg=PA225&dq=Harry Howard Webb mining engineer&source=bl&ots=_3rAmQa7hj&sig=ACfU3U1RTE6d24fjAYfZfcIeGKbd5vuUeA&hl=en&sa=X&ved=2ahUKEwjMjczv05vwAhXGN8AKHepMD4YQ6AEwEHoECBAQAw#v=onepage&q=Harry Howard Webb mining engineer&f=false
Chemical, Metallurgical and Mining Society of South Africa. Proceedings, 1899, Vol. 2 and 1903, Vol. 3: Lists of members.
Draper, J.R. The engineer's contribution: A history of the South African Institution of Mechanical Engineers, 1892-1967 (pp. 15, 245). Johannesburg: SAIME, 1967.
FamilySearch: Harry Howard Webb. https://ancestors.familysearch.org/en/K4GF-6P4/harry-howard-webb-1853-1939
Hall, A.L. A bibliography of South African geology to the end of 1920. Pretoria: Geological Survey, Memoir No. 18, 1922.
Men of the times: Pioneers of the Transvaal and glimpses of South Africa. Transvaal Publishing Company, 1905.
Orr, J. Presidential address. Associated Scientific and Technical Societies of South Africa, Annual Proceedings, 1938, pp. 15-86.
South African Association for the Advancement of Science. Report, 1903, 1904, 1905/6, 1910.
South African bibliography to the year 1925. London: Mansell, 1979.
Williams, A.F. American engineers in South Africa. Kimberley: Diamond Fields Advertiser, 1902, 19pp.