Zahrim, A. Y., A. Nazimah, and S. Rosalam. “Lignin Removal From Aqueous Solution Using Calcium Lactate: The Effect Of Polymers And Magnesium Hydroxide As A Flocculant Aids”. ASEAN Journal of Chemical Engineering, Vol. 14, no. 1, Dec. 2014, pp. 25-36, https://jurnal.ugm.ac.id/v3/AJChE/article/view/8476.