ปัญญายง ทวีสิทธิ์. “Electronic Lesson Development: Mathematics for ‘Long Lap Lae’ Durian Agricultural business in Uttradit Province: A Case Study of Moderate Class-More Knowledge Policy in Schools”. Ratchaphruek Journal 16, no. 1 (April 20, 2018): 30–36. accessed August 26, 2026. https://so05.tci-thaijo.org/index.php/Ratchaphruekjournal/article/view/125218.