Paramitha, Diyen, Zuhdan Kun Prasetyo, Jumadi Jumadi, and Anggi Namira Siregar. “The Influence of Use of Problem-Based Learning E-Book Materials of Optical Equipment on Improving Students’ Critical Thinking Ability”. Jurnal Penelitian Pendidikan IPA 9, no. 11 (November 25, 2023): 9149–9155. Accessed September 10, 2024. https://jppipa.unram.ac.id/index.php/jppipa/article/view/5165.