Kuznetsov, A., R. Serhiienko, D. Prokopovych-Tkachenko, Y. Tarasenko, and I. Belozertsev. “Algebraic Immunity of Symmetric Ciphers”. Computer Science and Cybersecurity, no. 4, Apr. 2018, pp. 36-48, https://periodicals.karazin.ua/cscs/article/view/10456.