[1]
A. O. . Siagian, Haudi, A. . Ariyanto, and H. . Wijoyo, “Online Learning in the Middle of the Covid-19 Pandemic ”, Nusantara Sci. Tech. Proc., vol. 2022, no. 16, pp. 75–81, Jan. 2022, doi: 10.11594/nstp.2022.1612.