Polruk, J., and P. Sukcharoen. “The Effectiveness of an Elderly Health Promotion Competency Enhancement Program on Elderly Health Promotion Competency Levels Among Undergraduate Nursing Students”. Nursing Journal CMU, vol. 49, no. 3, Sept. 2022, pp. 324-37, https://he02.tci-thaijo.org/index.php/cmunursing/article/view/256084.