Jindarattanawong, Jarassri. “The Development of a Training Model of Non-Formal Education, Based on Concepts of Constructionism and Self-Directed Learning to Enhance Functional Competencies of Personnel Officers in the Royal Thai Air Force”. Scholar: Human Sciences 3, no. 1 (October 16, 2014). Accessed April 29, 2024. http://www.assumptionjournal.au.edu/index.php/Scholar/article/view/279.