| Description | Contains photocopy of "Phase Shift Sinusoidally Alternating Colored Stimuli" by P L Walraven and H J Leebeek, in 'Journal of the Optical Society of America', vol. 54, number 1, (January 1964); photocopy of "Chromatic Stiles-Crawford Effect of Anomalous Trichromats" by P L Walraven and H J Leebeek, from "Letters to the Editor" section in 'Journal of the Optical Society of America', vol. 52, (July 1962); and a letter from George R Price to Walraven, 18 April 1964, asking for any literature on the Stiles-Crawford effect in anomalous trichromats. |