Delport JM Ds, NHK, Wapadrand, South Africa

Heron AIC Prof, Universität Erlangen-Nürnberg, Germany

Kuyper AC Ds, NHK, Villeria, South Africa

Otto J Dr, NHK, Newlands, Johannesburg, South Africa

Steenekamp NJS Ds, NHK, Middelburg, South Africa

Steenkamp CJH Ds, NHK, Mafikeng, South Africa

van de Beek A Prof, Vrije Universiteit van Amsterdam, The Netherlands

Van Deventer H Dr, NHK, Pretoria-Oos, South Africa

Van Wyk GMJ Dr, NHK, Vanderbijlpark, South Africa

Vroom HM Prof, Vrije Universiteit te Amsterdam, The Netherlands