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Any United States readers out there able to take a good quality high-res image of the back cover for us foreigners? Our covers are different, so we don't get a chance to solve the extra puzzles unless we get access to a good quality image.
Update: Thanks to Tim for sending in a scan of the back cover! For anyone like me, that can't access the US edition, here it is (click on the thumbnail to view full size - around 2MB in size):