Poolkaew, Ekachai, Raja Syed Tengku Sulaiman, and Panu Sriwisut. 2021. “PROBLEMS OF AMATEUR MUAYTHAI TRAINING OF INSTITUTE OF PHYSICAL EDUCATION”. Academic Journal of Thailand National Sports University 13 (2). Chonburi, Thailand:238-48. https://he02.tci-thaijo.org/index.php/TNSUJournal/article/view/250727.