Characteristics of other photochemical processes are cited, which might also pertain to those of the retina. By assuming such relationships for retinal receptors, hypothetical formulas are derived for conversion of tristimulus (CIE) values to physiological terms presumed to represent color perception. Substantial agreement between these physiological functions and actual observer response (ideal Munsell system) indicates a close degree of correlation. This approach is suggested as a basis for studying the problem of balanced perceptual color spacing.
E. HOYT DE KLEINE, "Quantitative Evaluation of Color Perception: An Hypothesis," J. Opt. Soc. Am. 48, 722-724 (1958)