List of sources:
A.J. Williams - a tropical veterinary pioneer. Journal of the Royal Society of Medicine, 2003, Vol. 96(9), pp. 465-466. Retrieved on 25 May 2021 from https://europepmc.org/article/pmc/pmc539607
Posthumus, P.J. Past veterinarians in South Africa (10th edition), Vol. 2, [1992].
Who was who, Vol. 4, 3rd ed. London: Adam & Black, 1964.
Williams, A.J. Poisonous plants in South Africa. Veterinary Record, 11 January 1902, pp. 421-422.