1. see, for example, D. B. Judd and G. Wyszecki, ‘Color in Business, Science and Industry’ 2nd ed., Wiley, New York (1963)
2. D. L. MacAdam, J. Opt. Soc. Am. 25 (1935) 249 and 361
3. F. J. Kahn, Appl. Phys. Lett. 20 (1972) 199
4. M. F. Schiekel and K. Fahrenschon, Appl. Phys. Lett. 19 (1971) 391
5. G. Assouline, M. Hareng and E. Leiba, Electron. Lett. 7 (1971) 699