List of sources:
British 1820 Settlers to South Africa. Transcribed marriage entries for WALKER. Retrieved on 7 April 2021 from https://www.1820settlers.com/genealogy/settlerbrowsemarrs.php?name=WALKER
FamilySearch: Philip Crampton Walker. https://ancestors.familysearch.org/en/K82C-8QM/philip-crampton-walker-1867-1909
Medical, dental and pharmacy register for the Transvaal, 1907.
National Archives Repository (TAB), Source MHG, Vol. 0, Ref. 16463: death notice, Philip Crampton Walker.
National Automated Archival Information Retrieval System (NAAIRS). http://national.archives.gov.za/naairs.htm Documents relating to Walker, Philip Crampton / Walker, Dr P.C.
Obituary: Philip Crampton Walker. South African Medical Record, 1910, Vol. 8, p. 10.
Transvaal civil service list, 1906.