Good suggestions one and all. The photo is owned by a photo journalist for National Geographic. A digital of the front side only was sent to a friend at UNL. He is asking if there is any other info (like a date) on the back.

I don't know what sort of temporal resolution he is needing, but all of these suggestions are good ones, and probably better than chasing down the shotgun. He just thought it would be fun to ask me because he knows I like old doubles.

Even more than old doubles, I like puzzles.

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BrentD, (Professor - just for Stan)
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[Linked Image from i.imgur.com]