1. 0. F. Vasil'ev and M. T. Gladyshev, ?Calculation of discontinuous waves in open channels,? Izv. Akad. Nauk SSSR, Mekh. Zhidk. Gaza, No. 6 (1966).
2. N. A. Kartvelishvili, Nonstationary Open Flows [in Russian], Gidrometeoizdat, Leningrad (1968).
3. Theory of Optimum Aerodynamic Shapes, Academic Press, New York (1965) (Russian translation published by Mir, Moscow (1969)).
4. G. A. Atanov, T. D. Ulanova, and A. V. Shipilin, ?A nozzle for obtaining maximal outflow velocity of a fluid,? in: Proc. Second All-Union Conf. on Optimal Control in Mechanical Systems [in Russian], Kazan' (1977).
5. A. N. Kraiko, ?On the solution of variational problems of supersonic gas dynamics,? Prikl. Mat. Mekh.,30, No. 2 (1966).