Roeth A.O.Najoan, Dwi Andriani Pamase and Mozes Yustus Legi (2026) “Implementation of the Problem-Based Learning (PBL) Model to Improve Mathematics Learning Outcomes of Third-Grade Students ”, ARMADA : Jurnal Penelitian Multidisiplin, 4(6), pp. 1311–1316. doi: 10.55681/armada.v4i6.2255.