Ferry, F., Livea, L., & Hendry, H. (2020). The Influence of Leadership, Motivation and Work Discipline on Employee Performance at PT Panjiwira Surya Mandiri Medan. Jurnal Mantik, 4(2), 1350-1355. https://doi.org/10.35335/mantik.Vol4.2020.949.pp1350-1355