Sichiangha , Aruntida, Pradidchaya Soijit, and Kosum Chansaengkrachang. “DEVELOPMENT OF LEARNING ACTIVITIES FOR MATHEMATICAL PROBLEM-SOLVING THROUGH GEOGEBRA PROGRAM WITH PLOBLEM-BASED LEARNING ACTIVITIES”. Journal of MCU Nakhondhat 8, no. 8 (July 31, 2021): 31–42. Accessed September 28, 2022. https://so03.tci-thaijo.org/index.php/JMND/article/view/254263.