S. Zuliani Nasution, Unita, Sahyar ., and Makmur Sirait. “EFFECT OF PROBLEM BASED LEARNING AND MODEL CRITICAL THINKING ABILITY TO PROBLEM SOLVING SKILLS”. Jurnal Pendidikan Fisika 5, no. 2 (December 1, 2016): 112–117. Accessed July 6, 2025. https://jurnal.unimed.ac.id/2012/index.php/jpf/article/view/4409.