A digital object identifier (DOI) is an alphanumeric code that is assigned to content to provide a persistent identifier (like a social security number for articles and chapters and other content). A DOI acts as a locator - helping individuals to find articles and chapters cited in bibliographies. DOIs are preferable to a URL in helping people find a specific article or chapter, because even if a URL for an article breaks in the future, the DOI will remain consistent.
At this point, more and more journal articles and other content types are assigned DOIs. DOIs are commonly seen on current electronic content, but may also be included in the print version of content. DOIs always begin with 10; however, a DOI can be expressed as a URL, where https://doi.org/ appears in front of the DOI. Here a couple of examples:
10.1111/j.1471-8847.2007.00193.x
https://doi.org/10.1101/102392
1. The DOI should be listed on the first page of a journal article. It is sometimes more difficult to find a DOI on a book or book chapter – check the title page verso. The DOI may or may not be prefaced with the letters DOI.
DOI on the Article First Page - Example 1
DOI on the Article First Page - Example 2
2. DOIs are often included in database records. Thus, when searching a library database like Academic Search Premier, SpringerLink, or CINAHL, if a DOI is assigned to an article, book, or book chapter, the DOI will be included in the database record.
DOI in a Database Record - Example 1
DOI in a Database Record - Example 2
3. DOIs may also be found in the bibliography of an article – as authors are now using DOIs as a citation tool. If you find a DOI in a bibliography and want to find the actual article, book, or book chapter (or at least further citation information), you need to use a DOI resolver (see http://dx.doi.org/).
4. Ask your librarian!