Patri Janson Silaban, Dewi Anzelina, Regina Sipayung, Rumiris Lumban Gaol, Dyan Wulan Sari HS, and Juliana. 2021. “Development of CAT-Based Student Worksheets to Improve Basic Students ’mathematical Understanding Abilities”. Elementary Education Online 20 (1):1062-70. https://ilkogretim-online.org/index.php/pub/article/view/3603.