Simanjuntak, Kesmi Veronika, and Bernieke Anggita Ristia Damanik. 2024. “THE EFFECT OF USING MOTHER TONGUE ON THE DEVELOPMENT OF COGNITIVE ABILITIES AND SECOND LANGUAGE IN EARLY CHILDHOOD”. Sindoro: Cendikia Pendidikan 8 (11):1-10. https://doi.org/10.9644/sindoro.v8i11.7547.