Danilin, A. R. Regularization of the control problem with constrained state. (English. Russian original) Zbl 0789.49025 Russ. Math. 36, No. 2, 24-28 (1992); translation from Izv. Vyssh. Uchebn. Zaved., Mat. 1992, No. 2(357), 24-28 (1992). MSC: 49N60 49K27