Saengrung, P., S. . Comesorn, and U. . Pumsanthia. “The Development of Learning Activities Based on the Tpack Concept of Graphs and Linear Relationships to Enhance Mathematical Conceptual Understanding of Seventh Grade Students”. Journal of Graduate Research, vol. 13, no. 2, Dec. 2022, pp. 71-86, https://so02.tci-thaijo.org/index.php/banditvijai/article/view/258015.