1. N. Wiener and R. Paley, Fourier Transform in the Complex Plane (Nauka, Moscow, 1964) [in Russian].
2. E. C. Titchmarsh, The Theory of Functions, 2nd ed. (Oxford University Press, London, 1958; Nauka, Moscow, 1980).
3. B. Ya. Levin, Distribution of Roots of Entire Functions (Gostekhizdat, Moscow, 1956) [in Russian].
4. A. G. Butkovskii, Control Methods for Systems with Distributed Parameters (Nauka, Moscow, 1975) [in Russian].
5. B. Ya. Levin, “On the Riesz Bases of Exponential Functions in L 2” Zapiski Matematicheskogo Otdeleniya Fiziki F-Ta Khar’Kovskogo Un-Ta I Khar’Kovskogo Matem. Obshchestva, Ser. 4. 27, 39–48 (1961).