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Referencing & Avoiding Plagiarism

DOI's: what they are and how to cite them!

Reference Management

What is a DOI?

A DOI, or Digital Object Identifier, is a string of numbers, letters and symbols used to permanently identify an article or document and link to it on the web. For example: DOI: 10.1016/j.jenvman.2021.112050. They are a source locator for online content.

They give each electronic, or digital, item (book, article) a unique, persistent identifier.

A DOI will assist the reader of your work to easily locate a document from your citation. It will always refer to that article, and only that one. While a web address (URL) might change, the DOI will never change.

Some referencing styles such as APA, Harvard ,Chicago, Vancouver and MLA recommend their use in citations.

The DOI is a shorter (as opposed to a URL) more convenient link to use in citations.

DOI's can be added in to EndNote and used in your bibliographies.

Note: Not all articles or resources have a DOI.

DOI's can be formatted in a number of different ways for example: 




Where is the DOI located?

In most recently published articles, the DOI will be printed with the article itself, usually on the first page somewhere, or in the header or footer. In the example below its in the footer.
If the DOI isn’t on the article, look it up on the website (use the “Search Metadata” option). You'll also find DOI's on Pubmed.





Digital Object Identifiers: A quick guide

What if my document doesn't have a DOI? Using persistent links

If your article doesn't have a DOI you can use the  permalink or persistant link option – this creates a tiny url which can be used in the reference without having long links.

Persistent Links will not expire as long as the content is available within the database. If the content is removed from the database, the Persistent Link will no longer be active.

A persistent link, also known as a durable link, stable link, or permalink, is a URL that connects directly to a specific full-text article in a library database or electronic journal subscription.

Many databases have an option for creating a persistent link. For example Library Search (see image above), ProQuest (Sociological Abstracts, E-book Central, ERIC), EBSCO (PsyInfo, Business Source Complete) and JSTOR Databases.

Persistent URLs (Document URLs)are designed so that your bookmarks and links don't break when a website gets updated. If you want to bookmark a study page or link to it from your website, you should bookmark/link the persistent URL.


How to find a DOI and What to do if there is no DOI

How do I cite a Journal Article with a DOI in it?

Referencing with DOI's and URL's using APA Style DOIs and URLs ( 

MLA Formatting & Style Guide MLA Formatting and Style Guide // Purdue Writing Lab  shows examples of referencing DOI's 

APA format?
In APA format, include the DOI for all works that have one. It goes at the end of your reference–no period at the end.

Author, A. A., & Author, B. B. (Date of publication). Title of article. Title of Journal, volume number, page range.

If your article has no DOI whatsoever, which may happen with older articles, simply omit this from the citation.

Author, A. A., & Author, B. B. (Date of publication). Title of article. Title of Journal, volume number, page range.

See these and other examples in the Purdue OWL: APA Formatting and Style Guide.

AMA/JAMA format?
When using a DOI in an AMA citation, do not include an “Accessed” date or a URL. Put the DOI at the end of your citation, prefaced with “doi:”

1. Author AA, Author BB. Title of article. Name of Jrnl. Year;vol(issue):inclusive pages. doi:10.0000000/000000000000

MLA format?
As of the most recent (8th) edition, MLA encourages students to include the DOI at the end of the citation for an online scholarly journal article. If no DOI exists, use the URL.

Author LastName, FirstName, and FirstName LastName. “Article Title.” Journal Name, vol. #, no. #, date, pp. ##-##. Name of Database, doi: 10.0000/000000000.

It’s a good idea to check with your instructor whether they want you to include the date you accessed the article, although this is not required by MLA.

Examples sourced What is a DOI and how do I use them in citations? (  and MLA Formatting and Style Guide // Purdue Writing Lab 


DOI or URL? APA Style Guidelines