|Description||Photocopies of articles and offprints, annotated by Smith, comprising:|
"Color Vision: The Approach Through Increment Threshold Sensitivity" by W S Stiles, in 'Proceedings of the National Academy of Sciences of America', vol. 45, number 1, (January 1959);
"Field Trials of Color-Mixture Functions" by W S Stiles and G Wyszecki, in 'Journal of the Optical Society of America', vol. 52, number 1, (January 1962);
"Investigation of the Scopotic and Trichromatic Mechanisms of Vision by the Two-Colour Threshold Technique" by W S Stiles, from the 'Revue d'Optique', vol. 28, number 4, (1949).