D., S.-A. O., and E. F. Aransiola. “Protease Production by Aspergillus Niger in Solid State Fermentation Using Bambara Beans (Vigna Subterranean)”. The International Journal of Science & Technoledge, vol. 5, no. 8, Aug. 2017, http://internationaljournalcorner.com/index.php/theijst/article/view/123616.