Zainal, Azavitra, Norhaliza Abdul Wahab, and Mohd Ismail Yusof. 2023. “PLC-Based PID Controller for Real-Time PH Neutralization Process Using Palm Oil Mill Effluent”. IIUM Engineering Journal 24 (1):244-55. https://doi.org/10.31436/iiumej.v24i1.2366.