de Villiers, G., G. Viljoen, and H. Booysen. “Global Warming and Climate Change With Reference to South Africa. Some Perspectives”. Suid-Afrikaans Tydskrif Vir Natuurwetenskap En Tegnologie / <i>South African Journal of Science and Technology</I&gt;, Vol. 27, no. 4, Sept. 2008, pp. 294-06, doi:10.4102/satnt.v27i4.98.