Kittivarakul, Veeris, Khawn Piasai, Sukanya Hajisalah, and Anek Janjaroon. “A STUDY OF MATHAYOMSUKSA III STUDENTS’ CONCEPTUAL KNOWLEDGE AND PROOF ABILITIES ON CIRCLE VIA CONJECTURING AND PROVING METHOD WITH GEOGEBRA PROGRAM”. Journal of Industrial Education 18, no. 2 (August 25, 2019): 67–74. Accessed March 28, 2024. https://ph01.tci-thaijo.org/index.php/JIE/article/view/179453.