1. L. V. Ahlfors, Conformal invariants, McGraw-Hill, 1973.
2. A. O. Gelfond, L. G. Schnirelman, Uspekhi Math., Nauk, No. 2, (1936) (Russian).
3. A. O. Gelfond, Comment “On determining the number of primes not exceeding the given values” and “On primes” in P. L. Chebicheff, Complete Works, v. 1., Academy, Moscow, 1946, 2nd printing (Russian).
4. Le Baron O. Ferguson, Approximation by polynomials with integral coefficients, Mathematical surveys #17, American Mathematical Society, Providence, 1980.
5. R. M. Trigub, Metric questions of the theory of functions and mappings, No. 2., pp. 267–333, Naukova Dumka Publishing House, Kiev, 1971 ( Russian).