Q. How do I find an item's DOI number?

The DOI (Digital Object Identifier) can usually be found on the first page of an article, often at the top or bottom. For e-books, check the title or copyright page. If you found the book or article in a library database, you can use the citation helper to see if it includes a DOI. If it does not, and you can't find one on the item, it probably does not have one. You can also use Crossref to look for a DOI using the title and author here: https://www.crossref.org/guestquery/.

Related FAQ: How can I find an article with its DOI?