Tran, T. K., L. H. Phung, H. N. le, T. T. H. Nguyen, X. S. Nghiem, and V. T. Pham. “A Dynamic Model for Ultrasonic – Assisted Extraction of Bio-Active Compounds from Natural Products”. ASEAN Journal of Chemical Engineering, Vol. 12, no. 2, Dec. 2012, pp. 35-42, https://dev.journal.ugm.ac.id/v3/AJChE/article/view/8130.