Salsabila, Alika, Brenda Novita Br Panjaitan, and Siti Hafiza. “Big Book Development in Mathematics Lessons Student Learning Outcomes in Class 1 SDN 085138 Langkat”. International Journal of Students Education 1, no. 2 (January 23, 2024): 572–576. Accessed August 3, 2025. https://journal.berpusi.co.id/index.php/IJoSE/article/view/544.