List of sources:
Family: Octavius Bouchier Bowker / Mary Anne Stubbs http://1820settlers.com/genealogy/familygroup.php?familyID=F121&tree=master
Gunn, M. & Codd, L.E. Botanical exploration of southern Africa. Cape Town: Balkema, 1981.
Harvey, W.H. & Sonder, O.W. Flora Capensis (Vol. 3, Preface). Ashford, Kent: Lovell Reeve, 1894 (originally published 1865).
Mitford-Barberton, I. & Mitford-Barberton, R. The Bowkers of Tharfield. Oxford University Press, 1952.
National Automated Archival Information Retrieval System (NAAIRS). http://www.national.archives.gov.za/naairs.htm Documents relating to Mary Anne Bowker.