List of sources:
Geological Society of South Africa. Transactions, 1897, Vol. 2, Officers of the society; list of members.
Hall, A.L. A bibliography of South African geology to the end of 1920. Pretoria: Geological Survey, Memoir No. 18, 1922.
Maki, H. and Haarhoff,
J. Municipal engineers in Johannesburg and Pretoria before 1910. Retrieved from
http://dspace.nwu.ac.za/bitstream/handle/10394/3955/transd_v5_n2_a7.pdf?sequence=1&isAllowed=y
on 21 March 2017.
Men of the times: Pioneers of the Transvaal and glimpses of South Africa. Johannesburg: Transvaal Publishing Co., 1905.
National Automated Archival Information Retrieval System (NAAIRS). http://www.national.archives.gov.za/naairs.htm Documents relating to Grey, George R.
Rhodesia Scientific Association. Proceedings, 1906, Vol. 6(1), pp. 108-109, list of members.
Shorten, J.R. The Johannesburg saga. Johannesburg: J.R. Shorten, 1970.
Standard Encyclopaedia of southern Africa, Vol. 8, p. 227b. Cape Town: NASOU, 1970-1976.