1. Ermolov, I.N. and Lange, Yu.V., Nerazrushayshchii kontrol'. Spravochnik v 7-mi tomakh (Nondestructive Testing. Handbook in 7 Volumes.), Klyuev, V.V., Ed., vol. 3: Ultrasonic Testing, Moscow: Mashinostroenie, 2004.
2. GOST (State Standard) 21397-81: Nondestructive Testing. Set of Calibration Blocks for Ultrasonic Testing of Semi-Finished and Aluminum Alloy Products. Specifications, 1982.
3. Kruglov, L.D. and Grishina, V.M., A Set of Standard Specimens KSO-2 and its Measurement Assurance, Defektoskopiya, 1984, no. 5, pp. 23–27.
4. Danilov, V.N., Ermolov, I.N, and Shcherbakov, A.A., Determination of the Vibration Frequency in Nondestructive Testing, Defektoskopiya, 2003, no. 3, pp. 3–11 [Rus. J. of Nondestructive Testing (Engl. Transl.), 2003, vol. 39, no. 3, p. 171].
5. Yavorskii, B.M. and Detlaf, A.A., Spravochnik po fizike dlya inzhenerov i studentov vuzov (Handbook on Physics for Engineers and Students of Colleges), Moscow: Nauka, 1968.