Abikoye, O. C., G. K. Afolabi, and T. O. Aro. “BIOMETRIC BASED POINT- OF- SALE AUTHENTICATION SYSTEM”. International Journal of Software Engineering and Computer Systems, vol. 5, no. 1, Feb. 2019, pp. 36-51, https://journal.ump.edu.my/ijsecs/article/view/2720.