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"What is Soft State". IGI-Global.com. Retrieved 2016-11-24. http://www.igi-global.com/dictionary/soft-state/27636
Ji, Ping (2003). "A Comparison of Hard-state and Soft-state Signaling Protocols". Computer Science Department Faculty Publication Series. Paper 199. University of Massachusetts - Amherst. http://scholarworks.umass.edu/cgi/viewcontent.cgi?article=1198&context=cs_faculty_pubs
Lui, J. C. S.; Misra, V.; Rubenstein, D. (2004). "On the robustness of soft state protocols". Proceedings of the 12th IEEE International Conference on Network Protocols, 2004. ICNP 2004. p. 50. doi:10.1109/ICNP.2004.1348084. ISBN 0-7695-2161-4. 0-7695-2161-4