Sajjapong, W., K. Jongsomchai, U. Sadjapong, and P. Sooksaen. “Effects of promoting eating foods containing bitter vegetables on nutritional status in the elderly”. Journal of Associated Medical Sciences, vol. 57, no. 1, Nov. 2023, pp. 135-41, https://he01.tci-thaijo.org/index.php/bulletinAMS/article/view/264413.