Siregar SA, Nuraina N, Ningtiyas FA. The Effect of the Problem-Based Learning Model with a Metacognitive Approach on Students’ Mathematical Representation Ability. JIKT [Internet]. 2026Oct.20 [cited 2026Oct.23];17(2):323-39. Available from: https://www.chem-upr.education/ojs/index.php/JIKT/article/view/458