A librarian was working late one night at a small-town library. She had the door open for a breeze, and a chicken walked in, hopped up on the desk, and said, "Book, book, book!"
The librarian was a bit startled, but she quickly handed the chicken three books. The chicken put one under each wing, one in its beak, and walked out.
A few minutes later, the chicken returned, dropped those three books on the floor, hopped up on the counter, and said, "Book, book, book!"
Once again, the librarian gave the chicken three books, the chicken tucked one under each wing, took the third in its beak, and walked out.
It must be a full moon tonight, thought the librarian, getting back to her work. Of course, since everything in jokes comes in threes, the chicken came back. It dropped the books on the floor, hopped up, and said, "Book, book, book!"
This time, the librarian decided to get to the bottom of this. She gave three books to the chicken, and when it walked away, she followed it. They went across the parking lot, down into a ditch, and through a damp culvert.
Good thing I wore my sensible shoes, she thought.
They emerged into a little moonlit pool. There, the chicken stopped in front of the largest bullfrog the librarian had ever seen. He took one look at the books the chicken was carrying and croaked, "Read it, read it, read it!"