GAJANAN H. CHAVHAN, MANGESH S. DESHPANDE, RAJESH M. JALNEKAR. A comprehensive Investigation of Drought and Standard Precipitation Index (SPI). Mathematical Statistician and Engineering Applications, [S. l.], v. 70, n. 2, p. 419–432, 2023. DOI: 10.17762/msea.v70i2.1646. Disponível em: https://www.philstat.org/index.php/MSEA/article/view/1646. Acesso em: 19 may. 2024.