Old books often have a musty smell to them. If you want to remove the smell then have a go at the following.
You can remove odours with things such as baking soda, cat litter or charcoal. In order to remove the odor from books you will have to create a air tight container large enough to have the book(s) in and the odor absorbing material in.
The musty smell is generally caused by dampness, which in turn causes mould. If the books are damp then you need to dry them out. Place them upright on a table and fan the pages out. Place a fan to blow onto the pages to dry them out. Or just leave them in a dry room for a few days.
Then back to the container. It could be a large box or plastic container. Place the book(s) in there with a tray of baking soda, cat litter or charcoal briquettes. Leave the books in there for a couple of days and the smell should have gone.