Pujiastuti, Caecilia, et al. “Study of Effectiveness of Sodium Hydroxide (NaOH) and Sodium Carnonate (Na2CO3) on the Impurities Removal of Saturated Salt Solution”. Nusantara Science and Technology Proceedings, Aug. 2018, pp. 84-89, https://nstproceeding.com/index.php/nuscientech/article/view/19.