Siagian AO, Haudi, Ariyanto A, Wijoyo H. Online Learning in the Middle of the Covid-19 Pandemic . Nusantara Sci. Tech. Proc. [Internet]. 2022 Jan. 21 [cited 2025 Jul. 31];2022(16):75-81. Available from: https://nstproceeding.com/index.php/nuscientech/article/view/568