1. I. B. Esipov and A. V. Nikolaev, Akust. Zh. 51(Suppl.), 5 (2005) [Acoust. Phys. 51, S1 (2005)].
2. V. Yu. Zaĭtsev, V. É. Gusev, V. E. Nazarov, and B. Castagnede, Akust. Zh. 51(Suppl.), 80 (2005) [Acoust. Phys. 51, S23 (2005)].
3. V. S. Averbakh, V. V. Artel’nyi, B. N. Bogolyubov, V. V. Bredikhin, A. V. Lebedev, A. P. Maryshev, and V. I. Talanov, Akust. Zh. 54, 84 (2008) [Acoust. Phys. 54, 71 (2008)].
4. V. S. Averbakh, A. V. Lebedev, A. P. Maryshev, and V. I. Talanov, Akust. Zh. 54, 607 (2008) [Acoust. Phys. 54, 526 (2008)].
5. V. S. Averbakh, A. V. Lebedev, A. P. Maryshev, and V. I. Talanov, in Proc. of the XIXth RAO Session (GEOS, Moscow, 2007), Vol. 1, p. 328.