Apriyeni, Emira, and Helena Patricia. “The Improvement of Elderly Sleeping Quality With Progressive Muscle Relaxation Therapy”. International Journal Of Community Medicine And Public Health 7, no. 5 (April 24, 2020): 1684–1687. Accessed November 16, 2025. https://www.ijcmph.com/index.php/ijcmph/article/view/6266.