Van der Merwe, W.J.J.; Eicker, A.; Marasas, Walter F.O. (Walter Friedrich Otto); Kellerman, T. Stephanus(Published by The Government Printer, Pretoria, 1979)
Boomker, Jacob Diederik Frederik; Imes, G.D.; Cameron, Colin McKenzie; Naude, T.W.; Schoonbee, H.J.(Published by The Government Printer, Pretoria, 1979)