Pinheiro, Beatriz da Silveira, et al. “Carbon Isotope Discrimination and Yield of Upland Rice As Affected by Drought at Flowering”. Pesquisa Agropecuaria Brasileira, vol. 35, no. 10, Oct. 2000, pp. 1939-47, doi:10.1590/S1678-3921.pab2000.v35.5980.