Waangsir, F. W. .; Arnawa, I. G. P. .; Sadukh, J. J. .; Mauguru, E. M. . The Effectiveness of Reducing Hardness in the Filtration Process Using Mixed Media With Detention Time Variations. jppipa, pendidikan ipa, fisika, biologi, kimia 2023, 9, 11060-11064.