None; Boomker, Jacob Diederik Frederik(Pretoria : Agricultural Research Council, ARC-Onderstepoort Veterinary Institute and the University of Pretoria, Faculty of Veterinary Science, 2003)
None; Boomker, Jacob Diederik Frederik(Published jointly by the Agricultural Research Council, ARC-Onderstepoort Veterinary Institute and the Faculty of Veterinary Science, University of Pretoria., 2003)