1. Birks, A. S., Green, R. E. Jr., [Ultrasonic testing], 2nd ed. Columbus, (1991).
2. Hellier, Ch., [Handbook of Nondestructive Evaluation], McGraw-Hill, (2003).
3. The Way of Measurement of the Two-Port Network Stability Invariant Factors;Filinyuk;16th International Crimean Microwave and Telecommunication Technology Sevastopol Crimea,2006
4. Nondestructive testing: A guide in 7 volumes;Ermolov;Mechanical Engineering Moscow,2004
5. About the size of the near-field zone of the plane ultrasonic transducers, which are on the same axis;Kryukov;Acoustic Journal,1995