Sibagariang, Hartono, Ikhah Malikhah, and Ahmad Aswan Waruwu. “Analisis Disiplin Kerja, Kepuasan Kerja Dan Loyalitas Kerja Terhadap Kinerja Karyawan Pada PT Perkebunan Nusantara IV Regional I Medan”. Economics and Digital Business Review 6, no. 1 (February 7, 2025): 921–934. Accessed March 25, 2026. https://ojs.stieamkop.ac.id/index.php/ecotal/article/view/2215.