Klunklin , A. ., P. . . Sawasdisingha, P. . Juntasopeepun, S. . . Vichittragoonthavorn, S. . . Setteekul, and P. . Charoenpakdee. “THAI LANNA SPA ACCREDITATION CRITERIA DEVELOPMENT FOR WELLNESS TOURISM”. Dusit Thani College Journal, vol. 15, no. 1, Apr. 2021, pp. 431-53, https://so01.tci-thaijo.org/index.php/journaldtc/article/view/247460.