A white Penrose triangle.
Traced by <a href="//commons.wikimedia.org/wiki/User:Stannered" title="User:Stannered">User:Stannered</a>
2007-03-28
<a href="//commons.wikimedia.org/wiki/File:Pentriangle.png" title="File:Pentriangle.png">Image:Pentriangle.png</a>