1. Paithankar, Y. G. and Bhide, S. R. 2007.Fundamentals of Power System Protection, 26–55. New Delhi: Prentice Hall of India Private Limited.
2. Ravindranath, B. and Chander, M. 2006.Power System Protection and Switchgear, 75–91. New Delhi: New Age International (P) Limited.
3. Zeienldin, H., El-Saadany, E. F. and Salama, M. A. A novel problem formulation for directional overcurrent relay coordination. Large Engineering Systems Conference on Power Engineering 2004 (LESCOPE-04). 28-30 July, pp.48–52. Halifax, Canada
4. Optimal coordination of directional overcurrent relays in interconnected power systems
5. An on-line relay coordination algorithm for adaptive protection using linear programming technique