Utama, Aditya, Mohammad Pramono Hadi, and Emilya Nurjani. “Geographic Information Systems Application to Drought Distribution Identification With Standardized Precipitation Index (SPI) Method in Trenggalek Regency”. INTENSIF: Jurnal Ilmiah Penelitian dan Penerapan Teknologi Sistem Informasi 5, no. 2 (August 8, 2021): 266-278. Accessed March 29, 2024. https://ojs.unpkediri.ac.id/index.php/intensif/article/view/15645.