- Connect your Nook to your computer.
- In Adobe Digital Editions, click to view your Nook's library.
- Click the arrow in the upper left corner of the book cover. Select Return Borrowed Item.
- Do the same thing in the All Items bookshelf.

Links:
[1] http://www.lexpublib.org/taxonomy/term/1834
[2] http://www.lexpublib.org/taxonomy/term/1865
[3] http://www.lexpublib.org/taxonomy/term/1842