Bingham, J.; Jacobs, Jeanette Antonio; Jaftha, Julian Bernard(Published by the Agricultural Research Council, Onderstepoort Veterinary Institute, 1998)
Abu Elzein, E.M.E.; Aitchison, Henry; Al-Afaleq, A.I.; Al-Bashir, A.M.; Ibrahim, A.O.; Housawi, F.M.T.(Published by the Agricultural Research Council, Onderstepoort Veterinary Institute, 1998)