Togi Marito Santa Monika Manullang. “Pengetahuan Lanjut Usia Tentang Covid-19 Di Desa Simangulampe Kecamatan Baktiraja Kabupaten Humbang Hasundutan Tahun 2021”. Humantech : Jurnal Ilmiah Multidisiplin Indonesia 2, no. 2 (February 24, 2022): 269–282. Accessed July 3, 2024. https://journal.ikopin.ac.id/index.php/humantech/article/view/1331.