Werdani, Yesiana Dwi Wahyu. “The Effectiveness of Laughter Yoga to Improve Sleep Quality in Cancer Patients During COVID-19 Pandemic”. Public Health and Preventive Medicine Archive 10, no. 2 (December 1, 2022): 180–188. Accessed April 26, 2026. http://phpmarchive.org/index.php/phpma/article/view/330.