Marhamah Hasibuan A, Fauzi, Ermawati. Development of Differentiated Mathematics E-books Based on Langkat Malay Culture to Improve Students’ Functional Thinking and Critical Thinking Skills. JPLED [Internet]. 2025 Dec. 19 [cited 2026 Feb. 27];5(4):1268-79. Available from: https://digitalpress.gaes-edu.com/index.php/jpled/article/view/878