1. From the extensive literature on laser physics, we shall mention only a few recent textbooks: A. Yariv: Quantum Electronics, 3rd edn. ( Wiley, New York 1988 )
2. From the extensive literature on laser physics, we shall mention only a few recent textbooks: O. Svelto: Principles of Lasers, 3rd edn. ( Plenum, New York 1989 )
3. From the extensive literature on laser physics, we shall mention only a few recent textbooks: K. Shimoda: Introduction to Laser Physics, 2nd edn., Springer Ser. Opt. Sci., Vol. 44 ( Springer, Berlin, Heidelberg 1986 )
4. From the extensive literature on laser physics, we shall mention only a few recent textbooks: A.E. Siegman: Lasers ( University Science Books, Mill Valley, CA 1986 )
5. M. Garbuny: Optical Physics ( Academic, New York 1965 )