BASHE, M.; SHUMA-IWISI, M.; VAN WYK, M. A. Assessing the Costs and Risks of the South African Electricity Portfolio: A Portfolio Theory Approach. Journal of Energy in Southern Africa, [S. l.], v. 27, n. 4, p. 91–100, 2016. DOI: 10.17159/2413-3051/2016/v27i4a1545. Disponível em: https://energyjournal.africa/article/view/1545. Acesso em: 29 mar. 2024.