Games, 1984, N12
More than ten impossible figures were used in design of the cover. There are variations of impossible triangle, impossible trident and endless staircase. You can a variation of Shepard's impossible elephant as a deep on a book cover. Besides, take a look at cats which go through archimedian polyhedron then enter and go out from inlay on paper. This is the variation of M.C. Escher's litograph "Reptiles".