Chanmarlee, B., พานทอง ก. ., & Pradujprom, P. (2024). Enhancing Math Problem Solving Skills and Working Memory of Grade 3 Students using a Problem-based Learning Method Together with the Application of Abstract Code Model. Journal of MCU Phetchaburi Review, 7(1), หน้า 486 – 503. retrieved from https://so03.tci-thaijo.org/index.php/JPR/article/view/275275