Kuznetsov, A. ., N. . Poluyanenko, V. . Katrich, S. . Kandii, and Y. . Zaichenko. “Investigation of Heuristic Search Functions for Nonlinear Substitutions for Symmetric Cryptography”. Radiotekhnika, vol. 3, no. 206, Sept. 2021, pp. 53-63, doi:10.30837/rt.2021.3.206.05.