I had to read this line in the article twice:
"Initially, the assumption was that the notebooks had been misplaced. Librarians conducted searches over the next two decades..."
Two decades :)
"Initially, the assumption was that the notebooks had been misplaced. Librarians conducted searches over the next two decades..."
Two decades :)
Probably 20 years ago, they wouldn't have had all the security and CCTV that we have nowadays because it's so cheap.