Hwang S, Yeo S, Son T. A Comparative Analysis of Fraction Addition and Subtraction Contents in the Mathematics Textbooks in the U.S. and South Korea. IEJEE [Internet]. 2021 Apr. 24 [cited 2025 Nov. 13];13(4). Available from: https://iejee.com/index.php/IEJEE/article/view/1438