Hanif Fathur Rahman, S. Khuzaimah, and Arnesya Ramadhani, “Utilization of H₂SO₄ Activated PDAM Sludge as an Adsorbent with Alum Addition for Reducing COD and BOD in Batik Wastewater from Kutawaru, Cilacap”, J. ilm. Teknik. Kimia, vol. 10, no. 2, pp. 101–109, Jul. 2026.