Sholihah, Khoirur Rohmaniatush, and Djono. “Integration of Gamification and the Problem-Based Learning (PBL) Model in Chemistry Learning to Improve Critical Thinking Skills: A Literature Review”. Indonesian Journal of Learning and Instructional Innovation, vol. 3, no. 02, Dec. 2025, pp. 148-56, https://doi.org/10.20961/ijolii.v3i02.3009.