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2. 2. H. Bateman, A. Erdélyi, Higher Transcendental Functions, Vol. 2: Bessel Functions, Parabolic Cylinder Functions, and Orthogonal Polynomials, Nauka, Moscow (1974) [Russian translation]; McGraw-Hill, New York (1953).
3. 3. V. S. Vladimirov, Equations of Mathematical Physics [in Russian], Nauka, Moscow (1981).
4. 4. N. N. Vorob'ev, Theory of Series [in Russian], Nauka, Moscow (1979).
5. 5. V. F. Zheverzheev, L. A. Kal'nitskii, N. A. Sapogov, Special Course of Higher Mathematics for Higher Technical Educational Institutions [in Russian], Vysshaya Shkola, Moscow (1970).