Yayuk, Erna, Daroe Iswatiningsih, and Agung Deddiliawan Ismail. 2026. “Enhancing Mathematical Motivation, Problem-Solving, and Cognitive Engagement of Pre-Service Teachers: A Metaverse-Based Adaptive Gamification Research and Development Study”. International Journal of Learning, Teaching and Educational Research 25 (3):162-93. https://ijlter.myres.net/index.php/ijlter/article/view/2746.