França, A.F.S., and H.P. Haag. 1985. “ Mineral Nutrition of Tropical Grasses. I. Malnutrition Symptoms of N, P, K, CA, MG, S and B in Tobiatã (Panicum Maximum jacq.) ”. Anais Da Escola Superior De Agricultura Luiz De Queiroz 42 (1): 83-95. https://doi.org/10.1590/S0071-12761985000100007.