Green, L.; Gammon, D. W.; Hoffman, M. T.; Cohen, J.; Hilgart, A.; Morrell, R. G.; Verran, H.; Wheat, N. Plants, People and Health: Three Disciplines at Work in Namaqualand. S. Afr. J. Sci. 2015, 111 (9/10), 12. https://doi.org/10.17159/sajs.2015/20140276.