Makoto Sugita Mitsuru Kawazoe Ludovic Perret Hideki Imai Algebraic Cryptanalysis of 58-Round SHA-1. 349-365 2007 conf/fse/2007 FSE http://dx.doi.org/10.1007/978-3-540-74619-5_22 db/conf/fse/fse2007.html#SugitaKPI07