Srewongsitanon, K., and W. Techagaisiyavanit. “The Study of the Causes and Resolutions to the Illegal Establishment of Resorts Within a National Park: A Case Study of ThapLan National Park”. Journal of Humanities and Social Sciences, Rajapruk University, vol. 7, no. Special, Dec. 2021, pp. 147-58, https://so03.tci-thaijo.org/index.php/rpu/article/view/257378.