Trianda, Y., R. Desmiarti, T. Fujisawa, Y. Ishiguro, and F. Li. “Study of Suspended Impurities Origin and Composition in the Treatment Process of Johkasou System”. ASEAN Journal of Chemical Engineering, Vol. 18, no. 2, Dec. 2018, pp. 54-61, https://journal.ugm.ac.id/v3/AJChE/article/view/9024.