1. Rayleigh, L., The Theory of the Sound, 2nd Ed., Vol. 1, Dover, New York, 1945.
2. Suchy, K., "The velocity of wave packet in an anisotropic absorbing," J. Plasma Phys., Vol. 8, 33-51, 1972.
doi:10.1017/S0022377800006917
3. Bennett, J. A., "Complex rays for radio waves in an absorbing ionosphere," Proceedings IEEE, Vol. 62, 1577-1585, 1974.
doi:10.1109/PROC.1974.9665
4. Lipson, S. G. and H. Lipson, Optical Physics, Cambridge University Press, London, 1969.
5. Born, M. and E.Wolf, Principles of Optics, Pergamon Press Ltd., Oxford, 1965.
6. Sommerfeld, A., "About the propagation of light in dispersive media, in L. Brillouin," Wave Propagation and Group Velocity, 1960.
7. Loudon, R., "The propagation of electromagnetic energy through an absorbing dielectric," J. Physics A, Vol. 3, 233-245, 1970.
doi:10.1088/0305-4470/3/3/008
8. Garrett, C. G. B. and D. E. McCumber, "Propagation of a Gaussian light pulse through an anomalous dispersion medium," Phys. Review A, Vol. 1, 305-313, 1970.
doi:10.1103/PhysRevA.1.305
9. Chu, S. and S. Wong, "Linear pulse propagation in an absorbingmedium," Phys. Rev. Letters, Vol. 48, 738-741, 1982.
doi:10.1103/PhysRevLett.48.738
10. Censor, D. and J. J. Gavan, "Wave packets, group velocity, and rays in lossy media revisited ," IEEE Trans. Electromag. Compat., Vol. 31, 262-272, 1989.
doi:10.1109/15.30913
11. Sonnenschein, E., I. Rutkevich, and D. Censor, "Wave packets, rays, and the role of real group velocity in absorbing media," Physical Review E, Vol. 57, 1005-1017, 1998.
doi:10.1103/PhysRevE.57.1005
12. Suchy, K., "Real Hamilton equations of geometrical optics for media with moderate absorption," Radio Science, Vol. 16, 1179-1182, 1981.
doi:10.1029/RS016i006p01179
13. Censor, D., "Alternative methods for ray propagation in absorbing," Proc. of IEEE, Vol. 69, 750-751, 1981.
doi:10.1109/PROC.1981.12054
14. Suchy, K., "The propagation of wave packets in inhomogeneous anisotropic media with moderate absorption," Proc. of IEEE, Vol. 62, 1571-1577, 1974.
doi:10.1109/PROC.1974.9664
15. Censor, D. and K. Suchy, "Wave packets and ray tracing in lossy media," Proc. URSI Natl. Comm., 617-623, 1975.
16. Censor, D., "Fermat’s principle and real space-time rays in absorbing," J. Phys. A: Math. and Gen., Vol. 10, 1781-1790, 1977.
doi:10.1088/0305-4470/10/10/012
17. Censor, D., "Fermat’s principle, Hamiltonian ray equations, group velocity and wave packets in absorptive media," Advances in Thermodynamics, Volume 3: Nonequilibrium Theory and Extremum, 1990.
18. Muschietti, L. and C. T. Dum, "Real group velocity in a medium with dissipation," Phys. Fluids B, Vol. 5, 1383-1397, 1993.
doi:10.1063/1.860877
19. Bolda, E. L., R. Y. Chiao, and J. Garrison, "Two theorems for the group velocity in dispersive media," Phys. Rev. A, Vol. 48, 3890-3894, 1993.
doi:10.1103/PhysRevA.48.3890
20. Smith, R. L., "The velocities of light," Am. J. Phys., Vol. 38, 978-984, 1970.
doi:10.1119/1.1976551
21. Bloch, S. C., "Eighth velocity of light," Am. J. Phys., Vol. 45, 538-549, 1977.
doi:10.1119/1.10953
22. Gurwich, I. and D. Censor, "On the propagation of electromagnetic waves with a multi-band spectrum in weakly nonlinear media," J. of Electromag. Waves and Appl. (JEWA), Vol. 10, 889-907, 1996.
doi:10.1163/156939396X00018
23. Gurwich, I. and D. Censor, "Existence problems in steady state theory for electromagnetic waves in weakly nonlinear media," J. of Electromag. Waves and Appl. (JEWA), Vol. 9, 1115-1139, 1995.
24. Stratton, J. A., Electromagnetic Theory, McGraw-Hill, New York and London, 1941.
25. Landau, L. D., E. M. Lifshitz, and L. P. Pitaevskii, Electromagnetics of Continuous Media, Pergamon Press Ltd., Oxford, 1984.
26. Newell, A. C. and J. V. Moloney, Nonlinear Optics, Addison-Wesley Publishing Company, Redwood City, 1992.
27. Censor, D., "Dual approach for wave packets and solitary waves in nonlinear systems," Phys. Rev. A, Vol. 25, 437-447, 1982.
doi:10.1103/PhysRevA.25.437
28. Gurwich, I., "A novel approach to the nonlinear propagation of wide light beams," J. of Phys. D: Appl. Phys., Vol. 30, 2183-2190, 1997.
doi:10.1088/0022-3727/30/15/010
29. Band, Y. B., D. F. Heller, and J. S. Krasinski, "Spectrum of three-wave mixing for multimode fields," Phys. Rev. A, Vol. 40, 4400-4403, 1989.
doi:10.1103/PhysRevA.40.4400
30. Whitham, G. B., Linear and Nonlinear Waves, Wiley and Sons, New York, 1974.
31. Landau, L. D. and E. M. Lifshitz, "Quantum Mechanics: Non-Relativistic Theory," Pergamon Press Ltd., 1977.