1. D. F. Horne, in “Introduction to Optical Technology” (Crane-Russak Inc., New York, 1971) p. 25.
2. J. Ma. Fernandez Navarro, in “El Vidrio” (Consejo Superior de Investigaciones Cientificas, Madrid, 1985) p. 528.
3. G. P. Smith, J. Photographic Sci.
18 (1970) 41.
4. V. V. Vargin
et al., Soviet J. Opt. Technol.
35 (1968) 38.
5. A. V. Datsenko, Soviet J. Opt. Technol.
41 (1974) 395.