Sandro del Prete
The Torn Virtual Book
The torn piece of paper appears to be doubled; one section is folded upward, while its counterpart lies flat. If it were, in fact, a doubled piece of paper, it would be impossible to draw the book on the lower leaf. This is an impossible book design. Note that on the left side, part of the book is poking out of the frame, while on the right, the design is incomplete.