1. T.N. Verbitskaja-Variconds (Gosenergoizdat, Moscow-Leningrad, 1958), p. 63.
2. Ferroelectrics in Microwave Engineering, edited by O.G. Vendik (Moscow, ?Sov. Radio??, 1979), p. 272.
3. L.C. Sengupta and S. Sengupta, IEEE Trans. on Ultrasonics, Ferroelectrics and Frequency Control, 44(4), 792 (1997).
4. A.D. Kanareykin and E.A. Nenasheva, Russian Patent Application # 2003107001 (05.03.2003).
5. A.D. Kanareykin, W. Gai J.G. Power E.A. Nenasheva S.F. Karmanenko, in Proceedings of the Particle Accelerator Conference PAC-2003, (Portland, USA, to be published, 2003).