Mohd Zainuddin, Nur Ain, Nursyahzani Mohamad Sarwani, Siti Wahidah Puasa, and Kamariah Noor Ismail. “Reduction of Hexavalent Chromium to Trivalent Chromium Using Sludge from Acetylene Gas Production”. International Journal of Integrated Engineering 14, no. 5 (September 6, 2022): 178–187. Accessed May 17, 2024. https://publisher.uthm.edu.my/ojs/index.php/ijie/article/view/11939.