Heartwater : Past, Present and Future. Workshop (1986 : Kruger National Park, South Africa); Vermeulen, N.M.J.(Published by the Government Printer, Pretoria., 1987)
Heartwater : Past, Present and Future. Workshop (1986 : Kruger National Park, South Africa); Viljoen, Gerrit Johannes; Vermeulen, N.M.J.(Published by the Government Printer, Pretoria., 1987)
Heartwater : Past, Present and Future. Workshop (1986 : Kruger National Park, South Africa); Vermeulen, N.M.J.(Published by the Government Printer, Pretoria., 1987)