Siregar, Gurnal Rai Gandra, Munar Lubis, and Isti Ilmiati Fujiati. “Correlation Between Breastfeeding Duration and Motor Development in Children”. Sumatera Medical Journal 1, no. 1 (October 1, 2018): 6-10. Accessed May 6, 2024. https://talenta.usu.ac.id/smj/article/view/440.