List of sources:
British Association for the Advancement of Science. Report of the seventy-fifth meeting... South Africa, 1905, list of members.
Cape of Good Hope. Report of the Meteorological Commission, 1896, 1897, 1899-1903.
Cape Society of Civil Engineers. Minutes of Proceedings, 1903-1907, Vol. 1-5; 1909, Vol. 7.
Dictionary of South African biography, Vol. 4, 1981.
FamilySearch: Thomas Stewart, https://www.familysearch.org/ark:/61903/3:1:939Z-568J-Y?view=index&personArk=/ark:/61903/1:1:QLXQ-4RSZ&action=view&cc=1779109&lang=en&groupId= AND Thomas James Stewart, https://www.familysearch.org/en/tree/person/details/GPPG-L24
General directory and guide-book to the Cape of Good Hope and its dependencies, 1886, p. 109: Hydraulic engineer.
Hall, A.L. A bibliography of South African geology to the end of 1920. Pretoria: Geological Survey, Memoir No. 18, 1922.
Mendelssohn, S. South African bibliography. London, 1910.
National Automated Archival Information
Retrieval System (NAAIRS). http://national.archives.gov.za/naairs.htm Documents relating to Thomas Stewart.
Obituary: Thomas Stewart. Grace's Guide to British Industrial History. Retrieved on 10 December 2020 from https://www.gracesguide.co.uk/Thomas_Stewart
Rogers, A.W. The pioneers in South African geology and their work. Transactions of the Geological Society of South Africa, 1937, Annexure to Vol. 39, pp. 1-139 (see pp. 1 and 103).
Royal Society of London. Catalogue of scientific papers [1800-1900]. London: Royal Society, 1867-1925.
Royal Society of South Africa. Transactions, 1910-1924, Vol. 1, 3, 6 and 11.
South African bibliography to the year 1925. London: Mansell, 1979.
South African Philosophical Society. Transactions, 1883-1907, Vol. 3, 4, 6-10, 16, 17.
South African who's who, 1908, 1927/8, 1931/2, 1936, 1939.
University of the Cape of Good Hope. Calendar, 1884/5, 1896/7.