Prabandari, Fatchurrohmah Ines, Bhisma Murti, and Hanung Prasetya. 2021. “Associations Between Physical Activity, Depression, and Quality of Life in Elderly: Meta-Analysis”. Journal of Epidemiology and Public Health 5 (4):420-34. https://www.jepublichealth.com/index.php/jepublichealth/article/view/348.