Bragg, R.R. (Robert Richard)(Published jointly by the Agricultural Research Council, ARC-Onderstepoort Veterinary Institute and the Faculty of Veterinary Science, University of Pretoria., 2002)
Blaylock, R.S.M.(Published jointly by the Agricultural Research Council, ARC-Onderstepoort Veterinary Institute and the Faculty of Veterinary Science, University of Pretoria., 2001)