1. Nekrasov, A.I., On a Class of Linear Integro-Differential Equations, Tr. TsAGI, 1934, vol. 190, pp. 1–25.
2. Vigranenko, T.I., On a Boundary Value Problem for Linear Integro-Differential Equations, Zap. Leningr. Gorn. Inst., 1956, vol. 33, no. 3, pp. 177–187.
3. Dzhumabaev, D.S., Conditions for the Unique Solvability of a Linear Boundary Value Problem for an Ordinary Differential Equation, Zh. Vychisl. Mat. Mat. Fiz., 1989, vol. 29, no. 1, pp. 50–66.
4. Trenogin, V.A., Funktsional’nyi analiz (Functional Analysis), Moscow: Nauka, 1980.