Sasang, N., T. Chusak, and A. Jumneansuk. “Factors Associated with Happiness in Life among Elderly in Phra Nakhon Si Ayutthaya Province”. Journal of The Royal Thai Army Nurses, vol. 27, no. 1, Apr. 2026, pp. 616-24, https://he01.tci-thaijo.org/index.php/JRTAN/article/view/284493.