Orlekowsky, T., A. Levanets, S. van Wyk, and A. Venter. 2012. “The Presence of Sianobacteria and Algae in Biological Soil Crusts on South African Goldmine Tailings”. Suid-Afrikaans Tydskrif Vir Natuurwetenskap En Tegnologie / <i>South African Journal of Science and Technology</I&gt; 31 (1), 1 bladsy. https://doi.org/10.4102/satnt.v31i1.349.