Kamalrudin, M., L. L. Ow, and S. Sidek. “Requirements Defects Techniques in Requirements Analysis: A Review”. Journal of Telecommunication, Electronic and Computer Engineering (JTEC), vol. 10, no. 1-7, Feb. 2018, pp. 47-51, https://jtec.utem.edu.my/jtec/article/view/3594.