K. ZAMRI and S. N. RAHMAT, “Application of the Standardized Precipitation Index (SPI) in Identifying Extreme Events”, rtcebe, vol. 3, no. 1, pp. 987–996, Dec. 2021, Accessed: May 03, 2024. [Online]. Available: https://publisher.uthm.edu.my/periodicals/index.php/rtcebe/article/view/3060