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[1] M. Sh. Birman, M. Z. Solomyak, Spectral theory of self-adjoint operators in Hilbert space, Textbook, 2nd edition, Lan, Saint-Petersburg, 2010, 464 pp. (in Russian)
[2] N. D. Kopachevsky, Volterra integro-differential equations in Hilbert space, Special lecture course, FLP “Bondarenko O. A.”, Simferopol, 2012, 152 pp. (in Russian)
[3] S. G. Krein, Linear differential equations in Banah space, Nauka, Moscow, 1967, 464 pp. (in Russian) | MR
[4] S. G. Krein (editor), Functional analysis, Nauka, Moscow, 1972, 544 pp. (in Russian) | MR
[5] M. Sowa, “Cosine operator functions”, Rozpr. Math., 49 (1996), 1–47 | MR
[6] V. V. Vlasov, D. A. Medvedev, N. A. Rautian, “Functional differential equations in Sobolev space and their spectrum analysis”, Matematika, Sovremennye problemy matematiki i mekhaniki, 8, no. 1, Moscow State University, Moscow, 2011, 8–306 (in Russian)
[7] V. Volterra, Theory of functionals, integral and integro-differential equations, Dover Publications, New York, 2005, 288 pp. | MR
[8] S. Ya. Yakubov, Linear differential operator equations and their applications, Elm, Baku, 1985, 220 pp. (in Russian)