Description of Hand Washing and Mask Wearing Knowledge during the Pandemic in Grade 4-5 School Children at Dolok Nagodang State Elementary School in 2021 (Marni Olypia Sinaga, Lindawati Simorangkir, & Amnita Ginting , Trans.). (2022). Jurnal Indah Sains Dan Klinis, 3(2), 18-22. https://doi.org/10.52622/jisk.v3i2.50