Wahyudi, Didik, Winarto Reki, Hardhono ., and Suhartono Damas. “Relationship Between Levels of Serum 25- Hydroxyvitamin D With Gender and Visual Acuity Students of Junior High School”. International Journal of Research in Medical Sciences 8, no. 11 (October 28, 2020): 3870–3875. Accessed April 16, 2026. https://www.msjonline.org/index.php/ijrms/article/view/8711.