1. I. I. Eremin, Vl. D. Mazurov, and N. N. Astaf’ev, Improper Problems of Linear and Convex Programming (Nauka, Moscow, 1983) [in Russian].
2. A. N. Tikhonov and V. Ya. Arsenin, Solutions of Ill-Posed Problems (Nauka, Moscow, 1979; Wiley, New York, 1981).
3. F. P. Vasil’ev, Optimization Methods (MTsNMO, Moscow, 2011), Vols. 1, 2 [in Russian].
4. I. I. Eremin and N. N. Astaf’ev, Introduction to the Theory of Linear and Convex Programming (Nauka, Moscow, 1976) [in Russian].
5. A. V. Fiacco and G. P. McCormick, Nonlinear Programming: Sequential Unconstrained Minimization Techniques (Wiley, New York, 1968; Mir, Moscow, 1972).