A class of Illusion in which an object which is physically unrealizable is apparently depicted.
See also Freemish Crate, Home Plate, Illusion, Necker Cube, Penrose Stairway, Tribar
References
Cowan, T. M. ``The Theory of Braids and the Analysis of Impossible Figures.'' J. Math. Psych. 11, 190-212, 1974.
Cowan, T. M. ``Supplementary Report: Braids, Side Segments, and Impossible Figures.'' J. Math. Psych. 16, 254-260, 1977.
Cowan, T. M. ``Organizing the Properties of Impossible Figures.'' Perception 6, 41-56, 1977.
Cowan, T. M. and Pringle, R. ``An Investigation of the Cues Responsible for Figure Impossibility.''
J. Exper. Psych. Human Perception Performance 4, 112-120, 1978.
Ernst, B. Adventures with Impossible Figures. Stradbroke, England: Tarquin, 1987.
Harris, W. F. ``Perceptual Singularities in Impossible Pictures Represent Screw Dislocations.''
South African J. Sci. 69, 10-13, 1973.
Fineman, M. The Nature of Visual Illusion. New York: Dover, pp. 119-122, 1996.
Jablan, S. ``Impossible Figures.'' http://members.tripod.com/~modularity/impos.htm and ``Are Impossible Figures Possible?''
http://members.tripod.com/~modularity/kulpa.htm.
Kulpa, Z. ``Are Impossible Figures Possible?'' Signal Processing 5, 201-220, 1983.
Kulpa, Z. ``Putting Order in the Impossible.'' Perception 16, 201-214, 1987.
Sugihara, K. ``Classification of Impossible Objects.'' Perception 11, 65-74, 1982.
Terouanne, E. ``Impossible Figures and Interpretations of Polyhedral Figures.'' J. Math. Psych. 27, 370-405, 1983.
Terouanne, E. ``On a Class of `Impossible' Figures: A New Language for a New Analysis.'' J. Math. Psych. 22, 24-47, 1983.
Thro, E. B. ``Distinguishing Two Classes of Impossible Objects.'' Perception 12, 733-751, 1983.
Wilson, R. ``Stamp Corner: Impossible Figures.'' Math. Intell. 13, 80, 1991.