1. Scientific Services, Rand Water, Vereeniging, RSA
2. Scientific Services Unit, Capricorn District Municipality, Polokwane, RSA
3. Agricultural Research Council, OVR, Pretoria, RSA
4. Department of Water Environmental and Earth Sciences, Tshwane University of Technology, Pretoria, RSA
5. Department of Environmental Sciences, University of South Africa, Florida, RSA