Pitiya Yannarut และ Wandee Kasemsukpipat;Tongta Somchaipeng. (2022) A Study of Mathematical Concept of Mathayomsuksa 3 Students by Using a Concept Attainment Model. <i>Humanities and Social Sciences Journal of Pibulsongkram Rajabhat University</i>, <i>16</i>(2), 726 - 738.Pitiya Yannarut และ Wandee Kasemsukpipat;Tongta Somchaipeng. "A Study of Mathematical Concept of Mathayomsuksa 3 Students by Using a Concept Attainment Model". Humanities and Social Sciences Journal of Pibulsongkram Rajabhat University 16 (2022):726 - 738.Pitiya Yannarut และ Wandee Kasemsukpipat;Tongta Somchaipeng. A Study of Mathematical Concept of Mathayomsuksa 3 Students by Using a Concept Attainment Model. Pibulsongkram Rajabhat University:ม.ป.ท. 2022.