1. 1. Pascu ML (2000): Laser Physics. In: Lasers in Medicine and Dentistry, (Z. Simunovic, ed.), Vitagraaf d.o.o., Rijeka, Croatia, pp. 23 - 74.
2. 2. Schawlow AL, Townes CH (1958): Infrared and optical masers. The Physical Review, 104: 324 - 327.
3. 3. Bertinetto F, Pascu ML, Greco MA, Bisi M (1995): Studies on tunable lasers as sources for spectroscopy measurements. Proceedings of the Fourth Conference in Optics, ROMOPTO’96 (V. Vlad, ed.), 2461: 317 - 324.
4. 4. Yariv A (1971): Introduction to Optical electronics. Holt, Rinehart and Winston, New York, pp. 40 - 44.
5. 5. Verdeyen J. T. (1989): Laser Electronics, Prentice Hall Int. Ed..