In the book Real World Haskell, there's a non-programming-related puzzle in a footnote at the bottom of page 15, in the middle of a simple text-processing problem:
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Find or create a text file; let's call it quux.txt:*
$ cat quux.txt Teignmouth, England Paris, France Ulm, Germany Auxerre, France Brunswick, Germany Beaumont-en-Auge, France Ryazan, Russia
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* Incidentally, what do these cities have in common?
While I hope my abilities will prove sufficient to solve the book's programming problems, this little geography puzzle is beyond me. What do these seven cities have in common?