Dimitris Glynos Panayiotis Kotzanikolaou Christos Douligeris Preventing Impersonation Attacks in MANET with Multi-Factor Authentication. 59-64 2005 conf/wiopt/2005 WiOpt http://doi.ieeecomputersociety.org/10.1109/WIOPT.2005.42 db/conf/wiopt/wiopt2005.html#GlynosKD05