Ritonga, Maysaroh Ritonga, Maysaroh Ritonga, and dr. Zaldi Sp.M. “LEVEL OF KNOWLEDGE OF STUDENT IN SMA MUHAMMADIYAH01 MEDAN TO DECREASED VISUAL ACTIVITY”. JIMKI: Jurnal Ilmiah Mahasiswa Kedokteran Indonesia 8, no. 3 (February 21, 2021): 35-40. Accessed May 5, 2024. https://bapin-ismki.e-journal.id/jimki/article/view/250.