Inverted Faces

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Berault P , 1683 The Church of England Evidently Proved the Holy Catholick Church (London: Hodgkin)

Brewster D , 1826 “On the optical illusion of the conversion of cameos into intaglios, and of intaglios into cameos, with an account of other analogous phenomena” Edinburgh Journal of Science 4 99–108

Frisby J P , 1979 Seeing. Illusion, Brain and Mind (Oxford: Oxford University Press)

Gregory R , 1998 Mirrors in Mind (London: Penguin)

Johannsen D E , 1971 “Early history of perceptual illusions” Journal of the History of the Behavioral Sciences 7 127–140

Rock I , 1973 Orientation and Form (New York: Academic Press)

Thompson P , 1980 “Margaret Thatcher: a new illusion” Perception 9 483–484

Vitruvius , 1962 On Architecture translated by Granger F (London: Heinemann)

Wade N J , 1998 A Natural History of Vision (Cambridge, MA: MIT Press)

Wade N J , 2000 “An upright man” Perception 29 253–257

Whistler L , 1948 Rex Whistler 1905–1944. His Life and His Drawings (London: Art and Technics)

Whistler R , Whistler L , 1946 ¡OHO! Certain Two-faced Individuals now exposed by the Bodley Head. The Drawings of Rex Whistler. The Words by Laurence Whistler (London: Lane)

Whistler R , Whistler L , 1978 AHA (London: Murray)