1. M. Born andE. Wolf:Principles of Optics, Chap. X (New York, 1959).
2. M. Bertolotti, B. Daino andD. Sette:Nuovo Cimento,33, 1705 (1964).
3. M. Born andE. Wolf:Principles of Optics, Chap. X (New York, 1959).
4. R. A. Shorb:Proceedings Symposium Electromagnetic Theory and Antennas (Copenhagen, 1962),E. C. Jordan (Editor) (New York, 1963).
5. G. B. Parrent andT. J. Skinner:Optica Acta,8, 93 (1961).