A DOI is a digital object identifier and it’s associated with electronic content, most often academic journal articles. It is commonly placed in the top header or bottom footer of an article. If no DOI is listed, you can search the CrossRef website to try to find it.
- In the search box at the top, select "Search metadata".
- Search by title or author to see if you can find a DOI for your source. A DOI is preferred over a URL.
DOI versus URL
The APA Style website explains when to use a DOI versus a website address. Here are some of the basic rules:
For ebooks and online periodical articles found on the web:
- If the source has a Digital Object Identifier (DOI), include it.
- If the source does not have a DOI, cite the web address for the source (URL).
- It is OK to use a shortened DOI or URL as long as it works.
For online periodical articles found through a library subscription database:
- If the article has a Digital Object Identifier (DOI), include it. If a DOI is not listed on your source, try searching the CrossRef website.
- If the article has no DOI, do not include a URL or database information. The reference should be the same as the reference for a print version of the work.
- For works from databases that publish original, proprietary material available only in that database (such as the UpToDate database) or for works of limited circulation in databases (such as monographs in the ERIC database), include the name of the database or archive and the URL of the work. If the URL requires a login or is session-specific (meaning it will not resolve for readers), provide the URL of the database or archive home page or login page instead of the URL for the work. See the page on including database information in references for more information.
- It is OK to use a shortened URL or DOI as long as it works.