Oops. Sorry about extra character in the PNL url. That site has an
explanation of the unusual equation (I had a math teacher who used
to do the same thing to see if we were watching). The photo for the
stamp is the one from the AIP url or a good image is at http://www.thehistorynet.com/worldwarii/images/2000/0500_3l.jpg
A letter by Greg Huber on p. 53 of the Oct 5 2001 issue of Science also
discusses the problem.