Ismail, R., D. M. Said, N. Ahmad, M. P. Abdullah, M. Y. Hassan, and A. O. Idris. 2018. “Optimization Method for Voltage Sag Monitor Placement in Power System”. International Journal of Electrical Engineering and Applied Sciences (IJEEAS) 1 (1):71-80. https://ijeeas.utem.edu.my/ijeeas/article/view/3910.