Limited-edition hand inscribed in pencil lower margin Hand-signed "MC Escher" in pencil in the margin Catalogue raisonné: Bool #389 © The M.C. Escher Company B.V. Wikipedia article In the permanent collection of MoMA: https://www.moma.org/collection/works/61398?artist_id=1757&locale=en&page=1&sov_referrer=artist Escher has here united three different worlds into one impossible structure. Escher author and scholar Bruno Ernst described the people in this tour de force as the Uprighters - those whose heads point towards the top of the image; the Left-leaners, whose heads point toward the left; and Right-leaners, whose heads point right. At the center, a Right-leaner sits reading. Next to him a Left-leaner appears coming up from the basement with a sack slung across his back. The reader's floor becomes this stair-climbers wall. Note, too, that the right- and left-hand staircases have figures walking on both the top sides as well as undersides. At the top of the picture, a Right-leaner and Left-leaner both move to the right on the same staircase, but, even though they are moving in the same direction, one is walking up the stairs while the other is going down. Like Escher's other imaginary spatial constructions, which exist on paper, but never could in the real world, this image reminds us that nothing is really as it seems!