Kutsukutsa, R. T., Gasura, E., Mabasa, S., Ngadze, E., (2014). African Crop Science Journal 22(4), 275-280. African Crop Science Society, Kampala, Uganda. English language
Kandeler, R., Ullrich, W. R., (2009). Journal of Experimental Botany 60(11), 2955-2956. Oxford University Press, Oxford, UK. English language
Bhandari, M. R., Kawabata, J., (2005). Plant Foods for Human Nutrition 60(3), 129-135. Springer Science + Business Media, Dordrecht, Netherlands. English language
Matsushima, K., Nemoto, K., Nakashima, N., Dema, D., Thapa, L., Watanabe, A., Maegawa, F., Baba, T., Matsushita, G., (2006). Journal of the Faculty of Agriculture, Shinshu University 42(1/2), 37-46. Faculty of Agriculture, Shinshu University, Nagano, Japan. Japanese language
Galati, A., McKay, A., Tan, S. C. (2005) External factsheets, Government of Western Australia, 3 pp., English language