Gwali, S., J. B. L. Okullo, G. Eilu, G. Nakabonge, P. Nyeko, and P. Vuzi. “Folk Classification of Shea Butter Tree (Vitellaria Paradoxa Subsp. Nilotica) Ethno-Varieties in Uganda”. Ethnobotany Research and Applications, vol. 9, July 2011, pp. 243-56, https://ethnobotanyjournal.org/index.php/era/article/view/582.