1. US Patent 439 992 1954 / Rosen C.A.- 29.06.1954.
2. H.W. Katz (Ed.), Solid State Magnetic and Piezoelectric Devices, Wiley, New York, 1959.
3. Piezoelectric Transformers;Lavrinenko,1975
4. E.G. Smazhevskaya, R.A. Zhuchina, N.A. Podol'ner, The problem of the influence of the basic parameters of a piezoceramic material on the characteristics of experimental models of piezotransformers, in: Transmitters and Receivers of Ultrasonic Vibrations Part 2, LDNTP, 1966, pp. 22–35 (in Russian).
5. The equivalent electrical circuit for radial modes of piezoelectric ceramic disk with concentric electrodes;Munk;Philips Research Reports,1965