Beierle, Christof, Anne Canteaut, and Gregor Leander. “Nonlinear Approximations in Cryptanalysis Revisited”. IACR Transactions on Symmetric Cryptology 2018, no. 4 (December 13, 2018): 80–101. Accessed April 19, 2024. https://tosc.iacr.org/index.php/ToSC/article/view/7362.