Rosolem, C.; Malavolta, E.; Machado, J. Studies on Mineral Nutrition of Grain Sorghum: IX. Effects of Potassium . An. Esc. Super. Agr. Luiz de Queiroz 1980, 37 (1), 143-155. https://doi.org/10.1590/S0071-12761980000100010.