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Appointments. The Official Gazette, Colony and Protectorate of Kenya, 11 April
1923, p. 326. Retrieved from https://books.google.co.za/books?id=P-sGS14_6bwC&pg=PA326&lpg=PA326&dq=Robert Eustace Montgomery&source=bl&ots=XNTSX3RCAV&sig=qtLQWJCqTngP7GW4_qAuBGxbInA&hl=en&sa=X&ved=2ahUKEwicybapy9PeAhWDJFAKHXkzChEQ6AEwDXoECAQQAQ#v=onepage&q=Robert Eustace Montgomery&f=false on 2018-11-15.
Google scholar. http://scholar.google.co.za Publications by R.E. Montgomery.
Journal of the South African Veterinary Medical Association, 1927, Vol. 1(1), pp. 84-85: List of Presidents and List of Members.
Montgomery, R.E. On a form of swine fever occurring in British East Africa. Journal of Comparative Pathology and Therapeutics, 1921, Vol. 34, pp. 159-191, 242-262.
National Automated Archival Information Retrieval System (NAAIRS). http://www.national.archives.gov.za/naairs.htm Documents relating to R.E. Montgomery.
Posthumus, P.J. Past veterinarians in South Africa (10th edition), Vol. 1, .
Rhodesia Scientific Association. Proceedings, 1909, Vol. 9.
South African Association for the Advancement of Science. Report, 1918, list of members.
South African Journal of Natural History, 1920, Vol. 2(2), pp. 293-301, Roll of members [of the South African Biological Society].