Hutagaol, Kartini, Louise Saija, and Maru M. J. Panjaitan. “THE ING NGARSA SUNG TULADHA COOPERATIVE LEARNING MODEL AND STUDENTS’ PROBLEM SOLVING ABILITIES”. JOHME: Journal of Holistic Mathematics Education 3, no. 2 (May 7, 2020): 118–126. Accessed February 23, 2025. http://ojs.uph.edu/index.php/JOHME/article/view/2005.