Rosazley, R., M. Shazana, M. Izzati, A. Fareezal, I. Rushdan, and Z. Ainun. “CHARACTERIZATION OF NANOFIBRILLATED CELLULOSE PRODUCED FROM OIL PALM EMPTY FRUIT BUNCH FIBERS (OPEFB) USING ULTRASOUND”. Journal of Contemporary Issues and Thought, vol. 6, Sept. 2016, pp. 30-37, https://ejournal.upsi.edu.my/index.php/JCIT/article/view/1054.