Thongdee, Panyapon, Paladorn Suwannapho, and Kongrat Nualpang. 2022. “Effects of Problem-Based Learning Activity Management With DAPIC Problem-Solving Processes Affecting Problem-Solving and Mathematical Connection Skills of the Sixth-Grade Students”. Journal of Graduate School, Pitchayatat, Ubon Ratchathani Rajabhat University 17 (2):81-88. https://so02.tci-thaijo.org/index.php/Pitchayatat/article/view/255123.