Sihombing, Andy Tonggo Michael, Rolib Sitorus, and Higiya Nola Sembiring. “Implementation of Corporate Social Responsibility (CSR) Study at PT Kereta Api Indonesia (Persero) Regional Division I North Sumatera”. Indonesian Journal of Interdisciplinary Research in Science and Technology 2, no. 7 (July 30, 2024): 1159–1178. Accessed May 7, 2026. https://journal.formosapublisher.org/index.php/marcopolo/article/view/10619.