RT Journal Article SR Electronic T1 Physiology of Colour and Pattern Vision JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 499 OP 501 DO 10.1136/bjo.55.7.499-a VO 55 IS 7 YR 1971 UL http://bjo.bmj.com/content/55/7/499.2.abstract AB