Simanjuntak, K. V. and Damanik, B. A. R. (2024) “THE EFFECT OF USING MOTHER TONGUE ON THE DEVELOPMENT OF COGNITIVE ABILITIES AND SECOND LANGUAGE IN EARLY CHILDHOOD”, Sindoro: Cendikia Pendidikan, 8(11), pp. 1–10. doi: 10.9644/sindoro.v8i11.7547.