Poonthawe, P., S. Junprasert, C. Toonsiri, S. Rattanagreethakul, S. Intolo, and T. Luecha. “Factors Influencing COVID-19 Preventive Behavior among Older Adults in Eastern Thailand”. NU Journal of Nursing and Health Sciences, vol. 18, no. 1, Nov. 2023, pp. 36-52, https://he01.tci-thaijo.org/index.php/NurseNu/article/view/263093.