1. Korn, G. and Korn, T., Mathematical Handbook, McGraw-Hill, 1961.
2. Ryabov, Y.V., Grachev, M.I., Kamanin, D.V., Kuz-netsov, V.L., Koptelov, É.A., Libanova,O.N., Litvin, V.S., Matushko, V.N., Razin, V.I., Sadykov, R.A., Sobo-levskiǐ, N.M., and Fedchenko, V.A., Phys. Solid State, 2010, vol. 52, no. 5, p. 1021.
3. Vladimirov, V.S., Uravneniya matematicheskoi fiziki (Mathematical Physics Equations), Moscow: Nauka, 1981.