Ryan Glabb Laurent Imbert Graham A. Jullien Arnaud Tisserand Nicolas Veyrat-Charvillon Multi-mode operator for SHA-2 hash functions. 127-138 2007 53 Journal of Systems Architecture 2-3 http://dx.doi.org/10.1016/j.sysarc.2006.09.006 db/journals/jsa/jsa53.html#GlabbIJTV07