Siagian AR, Junita Amalia, Regina Ayunita Tarigan, Sahat Pandapotan Nainggolan, Yoli Agnesia. Optimalisasi Kemampuan Matematika Siswa Toba Melalui Kompetisi Del Mathematics And Science 2022. JPKMMC [Internet]. 2024 Jun. 11 [cited 2025 Sep. 12];3(6):30-6. Available from: https://journal.mandiracendikia.com/index.php/pkm/article/view/1145