Hunt for hidden books to mark World Book Night

Books have been hidden across East Yorkshire as part of a treasure hunt to mark World Book Night.
The county's library service will provide clues on social media to the locations.
People who discover the books are being asked to post about it online. Last year more than 270 were found.
Librarian Hayley Nicholson said it was about "bringing the joy of reading to the whole East Riding".
"Stories are such a worthwhile thing to share, and we can't wait to see all the lucky people who find our hidden books," she said.
"We want people to interact with others in their community too, so once you've read your found book, you can pass it on to a friend, family member, or even a complete stranger."
World Book Night, which was on Wednesday, is a national event that aims to encourage adults to start reading and celebrate the impact of books on people's lives, East Riding of Yorkshire Council said.
The books will remain hidden until they are all discovered. Clues will be posted on the library service Facebook page.
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