M. . Siahaan, S. . Pardede, L. L. . Silitonga, S. Maruli, R. . Lumbansiantar, and A. S. Sinaga, “Analysis of Factors Affecting Online Learning at Nommensen HKBP University of Medan”, EJEDU, vol. 4, no. 1, pp. 36–42, Jan. 2023.