Optical illusions form structures in which curious little men can go up stairs to get to a lower place, hang pictures on the ceiling, and walk on walls.
- ISBN10 0399215573
- ISBN13 9780399215575
- Publish Date 18 May 1989 (first published 1 February 1970)
- Publish Status Out of Print
- Out of Print 1 December 2016
- Publish Country US
- Imprint Penguin Putnam Inc
- Format Hardcover
- Pages 28
- Language English