D. Yuliana Sinaga. “The Effect Of Ralistic Mathematics Learning Model And Project-Based Learning Model On Problem Solving Ability And Motivation Of Students In Class V Private Sd Markus Medan Helvetia”. International Journal of Educational Research & Social Sciences 3, no. 2 (February 28, 2022): 590–600. Accessed November 7, 2024. https://ijersc.org/index.php/go/article/view/268.