Manik Lal Das Ashutosh Saxena Deepak B. Phatak Algorithms and Approaches of Proxy Signature: A Survey. 264-284 2009 9 I. J. Network Security 3 http://ijns.femto.com.tw/contents/ijns-v9-n3/ijns-2009-v9-n3-p264-284.pdf db/journals/ijnsec/ijnsec9.html#DasSP09