Nainggolan, Elfrida. “PENERAPAN PENDEKATAN CONCRETE PICTORIAL-ABSTRACT (CPA) UNTUK MENINGKATKAN SIKAP TANGGUNG JAWAB, KEMAMPUAN PENGUASAAN KONSEP, DAN KEMAMPUAN PEMECAHAN MASALAH MATEMATIKA DI SDS XYZ JAKARTA [THE APPLICATION OF THE CONCRETE-PICTORIAL-ABSTRACT (CPA) APPROACH TO IMPROVE RESPONSIBILITY, CONCEPTUAL UNDERSTANDING, AND MATHEMATICAL PROBLEM SOLVING SKILLS AT SDS XYZ JAKARTA]”. JOHME: Journal of Holistic Mathematics Education, vol. 6, no. 1, June 2022, pp. 107-21, doi:10.19166/johme.v6i1.4527.