His The molecular basis of visual excitation, 1968.
Harvard University gazette, Apr. 17, 1997 p. 1 (d. 4-12-97) p. 13 (b. 11-18-1906)
Wikipedia, viewed March 8, 2014 (George Wald (November 18, 1906-April 12, 1997) was an American scientist who is best known for his work with pigments in the retina. He won a share of the 1967 Nobel Prize in Physiology or Medicine...Wald was born in New York City...He received his Bachelor of Science degree from New York University in 1927 and his PhD in zoology from Columbia University in 1932...he identified vitamin A in the retina. In 1934, Wald went to Harvard University where he became an instructor, then a professor. Wald spoke out on many political and social issues and his fame as a Nobel laureate brought national and international attention to his views. He was a vocal opponent of the Vietnam War and the nuclear arms race)