by McCutcheon, K.R.G., Freese, J.A., Frean, J.A., Sharp, B.L., Markus, M.B.
Published in Transactions of the Royal Society of Tropical Medicine and Hygiene (01.05.1999)

by Govere, J.M., la Grange, J.J., Durrheim, D.N., Freese, J.A., Sharp, B.L., Mabuza, A., Mngomezulu, N., Bredenkamp, B.L.F.
Published in Transactions of the Royal Society of Tropical Medicine and Hygiene (01.11.1999)

by Freese, J.A., Sharp, B.L., Rossouw, E.J., Gous, E., Fay, S.A.&Markus, M.B.
Published in South African journal of science (01.07.1994)

by Freese, J.A., Markus, M.B.
Published in Transactions of the Royal Society of Tropical Medicine and Hygiene (01.07.1990)

by Freese, J.A., Sharp, B.L., Ngxongo, S.M. & Markus, M.B.
Published in South African medical journal (03.12.1988)

by Freese, J.A., Sharp, B.L., Ridl, F.C. & Markus, M.B.
Published in South African medical journal (18.06.1988)