Upper Bounds on the Error Probability for Discrete Memoryless Channels with Feedback

The upper bound on the error probability from [K. Sh. Zigangirov, Probl. Inf. Trans., 1970, vol. 6, no. 2, pp. 159–163; A. G Dyachkov,Probl. Inf. Trans., 1972, vol. 8, no. 4] for block transmission of discrete messages over a symmetrical discrete memoryless channel with a binary input and with complete feedback are generalized to the case of a $K$-ary symmetrical memoryless channel and an arbitrary discrete memoryless channel with a binary input.