M. Sofyan Hasan Lubis, Yohny Anwar, and Muhammad Isa Indrawan. 2022. “Employee Performance Improvement at PT Cahaya Abadi Terang Medan Is Based on the Work Environment, Work Motivation, and Work Discipline”. SIASAT 7 (4), 261-70. https://doi.org/10.33258/siasat.v7i3.130.