[math-fun] History of packing 27 cuboids into a cube.

I have a puzzle by Tom Lensch. 27 AxBxC cuboids, to pack into a cube of side A+B+C. I know I've seen this puzzle written up somewhere, but I can't remember where, now. I want to add the history to a interactive demonstration I made for the problem: http://demonstrations.wolfram.com/BoxPacking/ --Ed Pegg Jr