1. PhD, Department of Agricultural Economics, Extension & Rural Development, University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa.
2. Associate Professor, Bureau for Food and Agricultural Policy (BFAP), University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa.
3. Professor, Centre for Environmental Economics and Policy Analysis (CEEPA), University of Pretoria, Private Bag X20, Hatfield, Pretoria 0028, South Africa.