Pachimsawat, P. “A Study of Personal Characteristics, Leadership, and Workplace Environment Affecting Work Achievement of In-Bound Tourist Guide (Foreign Language-Specific Area)”. Journal of Cultural Approach, vol. 16, no. 30, Dec. 2015, pp. 28-40, https://so02.tci-thaijo.org/index.php/cultural_approach/article/view/58385.