As the almost-spouse of a librarian, I must ask: where did you find that wonderful amazing object?
I inherited it, actually -- my father had a large collection of various posters from the world wars, and this is the one I kept and just recently got framed. I don't know where he got it, but he didn't really seem to value this one much -- he'd had others framed or stored carefully, but this one was stapled to the wall of his shop. I thought it deserved better.There's some info about this poster available on the web, such as this library catalogue entry. (And if you need a gift, somebody's selling reproductions via eBay.)
And as a real live librarian, I must say: this is terrific! What a great image.