Syahputri, Ziana, Sutarman, and Machrani Adi Putri Siregar. 2024. “Determining The Optimal Number of K-Means Clusters Using The Calinski Harabasz Index and Krzanowski and Lai Index Methods for Groupsing Flood Prone Areas In North Sumatra”. Sinkron : Jurnal Dan Penelitian Teknik Informatika 8 (1):571-80. https://doi.org/10.33395/sinkron.v9i1.13246.