1. L. M. Brekhovskikh and V. V. Goncharov,Introduction to Continuum Mechanics [in Russian], Nauka, Moscow (1982).
2. S. A. Gabov and A. G. Sveshnikov,Problems of Dynamics of Stratified Fluid [in Russian], Nauka, Moscow (1986).
3. J. Lighthill,Waves in Fluids, Cambridge Univ. Press, Cambridge (1978).
4. J. S. Turner,Buoyancy Effects in Fluids, Cambridge Univ. Press (1973).
5. N. H. Thomas and T. N. Stevenson, “A similarity solution for viscous internal waves,”J. Fluid Mech.,54, Part 3, 495–506 (1972).