Indra Setiawan, Dewi, and Muhammad Yahya Matdoan. “Cluster Analysis of Districts and Cities in North Sumatra Province Based on Socio-Economic Indicators”. Journal of Statistics and Data Analytics, vol. 1, no. 1, Sept. 2026, pp. 1-9, https://gammabeta.id/ojs/index.php/jsda/article/view/63.