GOH, KIAT YONG, and Aimi Syammi Binti Ab Ghafar. “Handwritten Digit Recognition System Using Convolutional Neural Network (CNN)”. Progress in Engineering Application and Technology, vol. 2, no. 1, June 2021, pp. 578-92, https://penerbit.uthm.edu.my/periodicals/index.php/peat/article/view/960.