Zahrim, A. Y., A. Nasimah, 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. 2, Dec. 2014, pp. 19-27, https://dev.journal.ugm.ac.id/v3/AJChE/article/view/8849.