Theorem on the alternative for a nonstationary differential encounter-evasion game : PMM vol. 42, no. 6, 1978, pp. 1123–1126

A position encounter-evasion differential game with non-stationary geometric constraints on the players' controls is analyzed. It is proved that the alternative is valid for this game, stating that either the position encounter game or the position evasion game is always solvable. The proof uses constructions analogous to the corresponding ones from [1].