1. V. N. Krupskii and V. E. Plisko, Theory of Algorithms (Akademiya, Moscow, 2009).
2. V. A. Uspenskii, Lectures on Computable Functions (Fizmatgiz, Moscow, 1960).
3. E. Specker, ‘‘Nicht konstruktiv beweisbare Sätze der Analysis,’’ J. Symbolic Logic 14, 145–158 (1949). doi 10.2307/2267043
4. M. B. Pour-El and J. I. Richards, Computability in Analysis and Physics (Springer-Verlag, Berlin, 1989).
5. P. Henrici, Discrete Variable Methods in Ordinary Differential Equations (Wiley, New York, 1962).