Purba, P. Y., R. V. Houten, N. R. S. Siahaan, M. Y. Nababan, and D. C. Sinaga. “The Influence of Leadership Style, Communication, and Work Discipline on Employee Performance of PT Sinar Gunung Sawit Raya”. International Journal of Social Science and Business, vol. 6, no. 2, June 2022, pp. 275-81, doi:10.23887/ijssb.v6i2.46365.