Sari, Silvie Permata, Yanwirasti Yanwirasti, and Desmawati Desmawati. “Relationship Between Topography of the Residential Area of Breastfeeding Mothers With Zinc and Calcium Level in Breast-Milk in West Sumatera”. International Journal of Research in Medical Sciences 7, no. 5 (April 26, 2019): 1833–1836. Accessed October 12, 2025. https://www.msjonline.org/index.php/ijrms/article/view/6330.