Pin Lin Wenling Wu Chuankun Wu Security Analysis of Double Length Compression Function Based on Block Cipher. 121-127 2007 4 I. J. Network Security 2 http://ijns.femto.com.tw/contents/ijns-v4-n2/ijns-2007-v4-n2-p121-127.pdf db/journals/ijnsec/ijnsec4.html#LinWW07