There's a section in "Surely you're joking, Mr. Feynman" about the Los Alamos library. Feynman was into safecracking as a hobby, but didn't get anywhere on the library's vault.
That's also sourced back to a book about the Manhattan Project: https://books.google.com.au/books?id=Ys0N4rFgt6UC&pg=PA160&l...