Suryanti, R. Indrati, H. E. Irianto, and D. W. Marseno, “Comparison Study on the Extraction of Gelatin from Nila Fish (Oreochromis nilotichus) Skin Using Acetic Acid and Citric Acid”, Pak. J. Nutr., vol. 15, no. 8, pp. 777–783, Jul. 2016, doi: 10.3923/pjn.2016.777.783.