1.
Sianipar RS, Sijabat D, Simanjuntak B. The Effect of Problem-Based Learning (PBL) on the Critical Thinking Skills of Fourth Grade Students. ISIHUMOR [Internet]. 2026 Jan. 31 [cited 2026 Jun. 11];4(1):359-68. Available from: https://www.putrapublisher.org/index.php/isihumor/article/view/1495