A DOI (digital object identifier) is a unique alphanumeric string that identifies a specific source. Unlike URLs, DOIs are persistent and do not change.
DOIs are typically used for journal articles, but some books, data sets, and government publications also have DOIs.
DOIs are used when citing a source.
Examples:
Where do I find a DOI?
A DOI is often found on the first page of an article, the copyright page of a book, or in the database record. You may also be able to find DOIs by searching crossref.org.
What if I can't find a DOI?
Not all articles or sources have a DOI. If you can't find a DOI, then it is probably because it does not exist for the particular article or source.
