A. S. Chukhnov, S. N. Pozdnyakov, and N. N. Pangina, “Analysis of the understanding of the material of theoretical informatics in competitions and olympiads in informatics”, Comput. Tools Educ., no. 2, pp. 55–67, Apr. 2018, doi: 10.32603/2071-2340-2018-2-55-67.