Tee, Elok Robert, and N. Selvanathan. “Enhancing The Personal Identification Number Input As A Means Of Identification Signature”. Malaysian Journal of Computer Science 9, no. 1 (June 1, 1996): 37–41. Accessed May 18, 2024. https://ejournal.um.edu.my/index.php/MJCS/article/view/2966.