Krongyut , K., Poomvichuvech, D. and Suman, N. (2020) “Evaluation and Classification of the Recreation Opportunities Spectrum in Natural-Base Attractions, Chiang Rai Province”, Dusit Thani College Journal, 12(3), pp. 102–117. available at: https://so01.tci-thaijo.org/index.php/journaldtc/article/view/240951 (accessed: 16 September 2026).