1. Hydroacoustic Encyclopedy, Ed. by V. I. Timoshenko (Taganr. Gos. R. Univ., Taganrog, 1999), pp. 75–77 [in Russian].
2. J. L. Buttler, Patent USA No. 3378814.
3. V. A. Andebura, I. V. Vovk, A. I. Golovanenko, et al., USSR Inventor’s Certificate No. 466627, Byull. Izobret., No. 13 (1975).
4. I. M. Zadirenko and A. G. Kuz’menko, Akust. Zh. 28, 781 (1982) [Sov. Phys. Acoust. 28, 463 (1982)].
5. Manual on Hydroacoustics, Ed. by A. E. Kolesnikov (Sudostroenie, Leningrad, 1988), pp. 235–237 [in Russian].