Yohanis F. Tipawael, et al. “Progressive Muscle Relaxation Therapy As an Alternative for Managing Stress During the COVID-19 Pandemic in Yapen Islands Regency”. Proceeding of The International Conference of Inovation, Science, Technology, Education, Children, and Health, vol. 1, no. 1, Oct. 2021, pp. 145-52, https://icistech.org/index.php/icistech/article/view/103.