Gao, Yuan, Chun Guo, Meiqin Wang, Weijia Wang, and Jiejing Wen. “Beyond-Birthday-Bound Security for 4-Round Linear Substitution-Permutation Networks”. IACR Transactions on Symmetric Cryptology 2020, no. 3 (September 28, 2020): 305-326. Accessed October 25, 2020. https://tosc.iacr.org/index.php/ToSC/article/view/8704.