Ewan Fleischmann Michael Gorski Stefan Lucks Attacking 9 and 10 Rounds of AES-256. 60-72 2009 ACISP http://dx.doi.org/10.1007/978-3-642-02620-1_5 conf/acisp/2009 db/conf/acisp/acisp2009.html#FleischmannGL09