Huang, A., ‘FREEDM system - a vision for the future grid’, 2010 IEEE Power and Energy Society General Meeting, 25-29 July 2010, pp. 1–4. H. Farhangi, “The path of the smart grid”, Power and Energy Magazine, IEEE, vol.8, no.1, pp.18-28, January-February 2010.
 S. Chuang, C. Schwaegerl, “Ancillary Services for Renewable Integration,” Integration of Wide-Scale Renewable Resources into the Power Delivery System, CIGRE/IEEE PES Joint Symposium, Jul 2009.
 M. Vitins, “A fundamental concept for high speed relaying”, IEEE Trans. Power Apparatus and systems, vol. 100, pp.163-173, 1981.
 A.F. Elneweihi, E.O. Schweitzer III, M.W. Feltis, “Negative-Sequence Overcurrent Element Application and Coordination in Distribution Protection,” IEEE /PES Summer Meeting, Seattle, WA, July 1992.
 Bill Fleming, “Negative-sequence impedance directional element,” SEL,1999.
 M. Baran, M. Steurer “A digital testbed for FREEDM system development”, IEEE Power and Energy Society general meeting, pp. 1-3, July 2010.
 G. G. Karady, Varun Iyengar, “Feasibility of Fast Pilot Protection for Multi-Load Distribution Systems,” PES General meeting 2012, pp-132-40.
 P. G. McLaren, E. Dirks, R. P. Jayasinghe, I. Fernado, G. W. Swift and Z. Zhang, "A positive sequence directional element for numerical distance relays", Proc. Conf. Developments in Power System Protection, pp. 239 -242 1997.
 SEL 351S-7 protection system instruction manual, SEL, SEL Notes, 2004, pp-192.
 SEL 3031 Serial Radio Transceiver instruction manual, SEL Technical Notes, 2013, pp-85.