File:Concrete Mathematics - Cover.png

Summary
source: http://www.informit.com/ShowCover.aspx?isbn=0201558025&type=c

Fair use rationale
The copyright is held by Addison-Wesley Publishers. The image is used in Concrete mathematics to illustrate the cover of the book. IT does not impede the ability of the publisher to market the book and is of quality too low for photographic reproduction.