Finding DOI Numbers

When looking for DOI numbers, you can:

  1. Check the first page of the article;
  2. Search the article’s title in CrossRef; OR
  3. Google the article’s title, open the publisher’s website from the results list, and look for the DOI number.

Can’t Find a DOI Number?

Not all articles have DOI numbers because DOI numbers:

  • Are optional.
  • Emerged in 2000, so articles published 20 or more years ago will not have DOI numbers.

If you checked the article, CrossRef, and the publisher’s website and did not find a DOI, there probably isn’t one, so you don’t need it in your citation.

Why Use DOI Numbers?

  1. The purpose of a DOI number is to make an item more easily retrievable. In fact, you can search for information about a DOI number on
  2. Many citation styles, such as APA, require DOI numbers whenever available.

What Are DOI Numbers?

DOI (digital object identifiers) are unique numbers, which are assigned to specific books, videos, and images—but you will see them primarily on academic journal articles.