Siahaan, R. and Rajagukguk , H. . . (2021) “Students Barriers in Online Learning of Covid 19 Pandemic for Fifth Grade in English Language Study Program of Sisingamangaraja XII University Tapanuli”, Jurnal Mantik, 5(3), pp. 1944-1947. Available at: https://iocscience.org/ejournal/index.php/mantik/article/view/1805 (Accessed: 21April2026).