Weber, O.L.S. and Haag, H.P. 1984. Mineral nutrition of Panicum maximum cv. Makueni I: growth, concentration and accumulation of the macronutrients . Anais da Escola Superior de Agricultura Luiz de Queiroz. 41, 2 (Jan. 1984), 761–793. DOI:https://doi.org/10.1590/S0071-12761984000200014.