Klinpudtan น. “The Correlation Between Self-Management and Happiness Levels of Heart Disease in The Community-Dwelling Old Population of Phetchaburi Province”. Journal of The Royal Thai Army Nurses, vol. 23, no. 1, May 2022, pp. 217-25, https://he01.tci-thaijo.org/index.php/JRTAN/article/view/240567.