Muhammad Gunawan and Rahmad Hidayat (trans.) (2021) “Determination of Zinc Level of Catfish (Clarias Batrachus) From Sei Sikambing Market by Visible Light Spectrophotometry”, Jurnal Indah Sains dan Klinis, 2(2), pp. 22–28. doi:10.52622/jisk.v2i2.22.