These sheets are effectively the first and last sheets in your book. (editiononebooks.com)
Starting at Level 2 can be used for all levels by letting the pupils produce their own number sets on last sheet (tes.com)
There are models of e-book readers in which on a bookshelf the special icon if the book has already been read is shown (in the course of reading has been reached last sheet), and icon (or percent) if the book has been opened and do not read to the end. (e-ink-reader.ru)