Malavolta, E. and Carvalho, J.G. de 1982. Foliar diagnosis in sugar cane: VII - effect of rainfall on the leaf level of Ca, Mg, and S in the plant cane . Anais da Escola Superior de Agricultura Luiz de Queiroz. 39, 1 (Jan. 1982), 109–116. DOI:https://doi.org/10.1590/S0071-12761982000100007.