1. G. Wyszecki and W. Stiles: Color Science: Concepts and Methods, Quantitative Data and Formulae (Wiley, New York, 1982) 2nd ed., pp. 451 and 633.
2. R. M. Boynton and P. K. Kaiser: Human Color Vision (J. Opt. Soc. Am. 1996) 2nd ed., p. 249.
3. L. M. Hurvich: Color Vision (Sinauer Associates, Massachusetts, 1981) Chap 11.
4. R. L. DeValois and K. K. DeValois: Vision Res. 33 (1993) 1053.
5. S. L. Guth: J. Opt. Soc. Am. A8 (1991) 976.