Matzenauer, Ronaldo, et al. “Relationships Between Evapotranspiration of Corn and the Penman’s and Thornthwaite Formulas”. Pesquisa Agropecuaria Brasileira, vol. 18, no. 11, Apr. 2014, pp. 1207-14, doi:10.1590/S1678-3921.pab1983.v18.15463.