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2. 2. G. Bateman, MHD Instabilities (MIT Press, Cambridge, MA, 1978; Energoizdat, Moscow, 1982).
3. 3. E. E. Gossard and W. H. Hooke, Waves in the Atmosphere: Atmospheric Infrasound and Gravity Waves: Their Generation and Propagation (Elsevier, Amsterdam, 1975; Mir, Moscow, 1978).
4. 4. N. V. Karlov and N. A. Kirichenko, Oscillations, Waves, Structures (Fizmatlit, Moscow, 2003) [in Russian].
5. 5. E. A. Coddington and N. Levinson, Theory of Ordinary Differential Equations (McGraw-Hill, New York, 1955; Inostrannaya. Literatura., Moscow, 1958).