1. J. F. Traub and H. Wozniakowski,A General Theory of Optimal Algorithms [Russian translation], Mir, Moscow (1983).
2. J. F. Traub, G. W. Wasilkowskii, and H. Wozniakowski,Information, Uncertainty, Complexity [Russian translation], Mir, Moscow (1988).
3. L. V. Kantorovich and G. P. Akilov,Functional Analysis [in Russian], Nauka, Moscow (1977).
4. S. V. Pereverzev and K. Sh. Makhkamov, ?Galerkin information, hyperbolic cross, and the complexity of operator equations,?Ukr. Mat. Zh.,43, No. 5, 639?648 (1991).
5. K. I. Babenko,Foundations of Numerical Analysis [in Russian], Nauka, Moscow (1986).