John M. Kennedy A Psychology of Picture Perception , London, 1974. More useful is his essay in J.Fisher ed. This is actually a fusion of two Goethe quotations by Max Raphael. I'm also indebted to his essay for the quotation from Faust which opens this site. There is a searchable imagebase containing hundreds of Durer prints held in the Fine Art Museums of San Francisco.
Prints hold a special place in the history of visual communication.