Wutthisas, Jare, Chaiyut Nateetorn, and Arnon Seesuk. 2018. “Concentrations of Radium-226 in Shawllow Well Waters and Bottled Waters in Surat Thani Province”. Journal of Health Science of Thailand 19 (6):921-29. https://thaidj.org/index.php/JHS/article/view/1550.