What is a doi?

A digital object identifier (doi) is a series of numbers and characters assigned permanently to any entity - for instance, a journal article - for use on digital networks, and it generally appears somewhere toward the end of an item record in a database. Here is an example of a doi:

10.1016/j.jada.2009.08.015

The current APA Style includes a doi as a standard part of a citation whenever it is available. You will see them in many of the examples in this guide. They are used to provide current information about an item, including where the item (or information about it) can be found on the Internet. To find a citation (and sometimes the full text) of an item by its doi, you can search at http://www.doi.org/ or http://www.crossref.org/.   Note: before paying a publisher for electronic access to an article, always consult with your librarian to see if your library already has access.