1. Die verwarming van huishoudelike water;Basson;National Building Research Institute, CSIR Report, Pretoria,1983
2. Energy efficiencies of heat pumps in residential buildings
3. Heat pump water heaters;Dobyn,1984
4. Potential of electrically operated heat pumps for heating water in South Africa;Johannsen;CSIR, Research Report 615, Pretoria,1986