List of sources:
Addresses and papers read at the joint meeting of the British and South African Associations for the Advancement of Science held in South Africa, 1905 (Vol. 3). Johannesburg: SAAAS.
British Association for the Advancement of Science. Report of the seventy-fifth meeting... South Africa, 1905. London: John Murray, 1906.
Chemical, Metallurgical and Mining Society of South Africa. Journal, 1905-1908, Vol. 6-8; 1920, Vol. 20, p. 129, (brief obituary note).
Dictionary of South African biography, Vol. 5, 1987.
FamilySearch: Donald Macaulay. https://www.familysearch.org/ark:/61903/3:1:3Q9M-CS4V-BSHF-9?view=index&personArk=/ark:/61903/1:1:QP8L-2QZN&action=view&cc=2520237&lang=en
Medical, dental and pharmacy register for the Transvaal, 1907.
National Automated Archival Information Retrieval System (NAAIRS). http://www.national.archives.gov.za/naairs.htm Documents relating to Donald Macaulay / Dr Macaulay.
Pietermaritzburg Archives Repository, Vol. NMC 34, [list of medical practitioners, etc., in the Transvaal, as on 31 December 1914].
South African Association for the Advancement of Science. Report, 1905/6, 1910: Lists of members.
Staats-almanak der Zuid-Afrikaansche Republiek, 1898, pp. 86-93, Naamlijst van de geadmitteerde genees-, heel- en Verloskundigen...
South African who's who, 1908, 1909, 1917/8, 1919/20.