The Depth Perception of the Duckling
in Richard D. Walk Papers, of University of Akron. Cummings Center for the History of Psychology; with Richard David Walk, 1920-1999, Series Four: Research Files, 1945-1997. Subseries One: Visual Cliff Research, 1958-1996, Box M4927, Folder 1: Visual cliff data - ducks, 1961-1962 , 11 page(s)