Unhalekka, Attadech, Numchai Supparerkchaisakul, and Polthep Poonpol. 2022. “Development of a Self-Transformational Leadership Scale for Medical Representatives in Thailand”. The Journal of Behavioral Science 17 (3):77-89. https://so06.tci-thaijo.org/index.php/IJBS/article/view/256791.