Marni Olypia Sinaga, Lindawati Simorangkir and Amnita Ginting (trans.) (2022) “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”, Jurnal Indah Sains dan Klinis, 3(2), pp. 18–22. doi:10.52622/jisk.v3i2.50.