Wongwarunyoo, Teerawat. 2020. “The Impact of the Patronage System on Performing the Civil Servant’s Duties in Loei Province”. Research and Development Journal, Loei Rajabhat University 15 (54):65-75. https://so05.tci-thaijo.org/index.php/researchjournal-lru/article/view/243206.