British Library mislays 9,000 books

"More than 9,000 books are missing from the British Library, including Renaissance treatises on theology and alchemy, a medieval text on astronomy, first editions of 19th- and 20th-century novels, and a luxury edition of Mein Kampf produced in 1939 to celebrate Hitler's 50th birthday. The library believes almost all have not been stolen but rather mislaid among its 650km of shelves and 150m items – although some have not been seen in well over half a century." - The Guardian