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Central model of the cube inversion.
(J.P.Petit 1991, imaging C.TARDY)
This is the polyhedral version of the central model of the sphere inversion according to B.Morin (see the article in the January 79 issue of Pour la Science).
Why "central model"? Because this model represents a cube, for example green on the outside and yellow on the inside, half-inverted. It therefore has "four ears", alternately green and yellow. If there is a sequence of transformations that can transform the cube into this model, the inversion is constructed, since it is enough to rotate the model 90° around its axis and then reverse all the transformations.