A solution to the problem is presented.
Collection of Mathematical Problems for Universities. In 4 Parts. Part 2. Special Topics in Mathematical Analysis: A Textbook for Universities/Bolgov V.A., Efimov A.V., Karakulin A.F., et al. Edited by A.V. Efimov and B.P. Demidovich. – 3rd ed., corrected. – Moscow: Nauka, Fizmatlit, 1995. – 368 p.
Krasnov M.A., Kiselev A.I., Makarenko G.I. Functions of a Complex Variable. Operational Calculus. Stability Theory. – Moscow: Nauka, Fizmatlit, 1971. – 254 p.