Sembiring H, Br Karo M. Test the Capability of the Down Flow-Up Flow Combination Filter Rate Lead (PB), Iron (FE) and Manganese (MN) which are Contained on Water Well Drill Public Residential Still Village Ndokum Siroga I Subdistrict Intersection Four Regency Karo . ijmst [Internet]. 2023Sep.15 [cited 2024Dec.21];10(3):2348-54. Available from: https://cosmosscholars.com/phms/index.php/ijmst/article/view/1962