If you are citing a print source and want to know if it has been assigned a DOI, use ’s DOI lookup on the website’s home page.ĭOIs differ from URLs in that they are static. Because DOIs are assigned when a source is published electronically, some older sources will not have DOIs.

DOIs also associate their publications with metadata, or relevant information related to each source (such as author, location, and date information). Every DOI begins with the number 10, and can generally be found on the first page of the digital article. The IDF, founded in 1998, handles creator requests for DOIs and standardizes each DOI they assign. When sources are published electronically, they are assigned DOIs-a unique series of letters and numbers set by the International DOI Foundation. This resource explains the difference between URLs and DOIs and briefly describes how to incorporate either form of information into your citations. You do not normally need to include both. While citation styles can vary greatly in their particulars, most major styles (including APA, MLA, and Chicago) require writers to include either a URL or a DOI in citations for digital content whenever possible.

A list of urls