Nattinan Srinukul และ Samart Aiyakorn; Chardchai Udomkijmongkol. (2022) Work Motivation Affecting Happiness at Work for the Personnel of the Ministry of Labor in the Upper Northeastern Region 2. <i>Interdisciplinary Academic and Research Journal</i>, <i>2</i>(5), 253-272.Nattinan Srinukul และ Samart Aiyakorn; Chardchai Udomkijmongkol. "Work Motivation Affecting Happiness at Work for the Personnel of the Ministry of Labor in the Upper Northeastern Region 2". Interdisciplinary Academic and Research Journal 2 (2022):253-272.Nattinan Srinukul และ Samart Aiyakorn; Chardchai Udomkijmongkol. Work Motivation Affecting Happiness at Work for the Personnel of the Ministry of Labor in the Upper Northeastern Region 2. DR.KEN Institute of Academic Development and Promotion:ม.ป.ท. 2022.