Hazmi, A., R. Desmiarti, E. P. Waldi, and P. Emeraldi. “Preliminary Study on Treatment of Palm Oil Mill Effluent (POME) by Sand Filtration-DBD Plasma System”. Journal of Engineering and Technological Sciences, vol. 48, no. 1, Feb. 2016, pp. 21-30, doi:10.5614/j.eng.technol.sci.2016.48.1.3.