Here's the article which was a 1964 Stanford AI Memo. After the original memo, several people offered different proofs of the theorem including Shmuel Winograd, Marvin Minsky and Dimitri Stefanyuk - none published, to my knowledge. Winograd claimed that his proof was non-creative, because it didn't use an extraneous idea like the colors of the squares. This set off a contest to see who could produce the most non-creative proof. Minsky's idea was to start with the diagonal next to an (...) excluded corner ssquare, note that 2 dominoes had to project from it to the diagonal with three squares, and from there 1 domino to the four square diagonal, etc. Coming from the other end also leaves only six of the eight squares in the long diagonal covered. Minsky's proof gets high points for non-creativity, because it is specific to the 8 by 8 board. (Using the colors it is easy to show that a Minsky style proof will work for any even sized board.). (shrink)