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Northern Studies: Thunder Bay

Cite Your Sources!

How do you cite your sources?

Check out our Zotero Guide and the Library's How to Cite Your Sources page.

Tips and Hot Topics

Example on how to write an annotated bibliography.

University of Toronto.  help page

DOIs and Citing your Sources in APA Format

What's a DOI?

A DOI is a Digital Object Identifier.

It is a unique alphanumeric string assigned by a registration agency (the International DOI Foundation) to identify content and provide a persistent link to its location on the Internet. The publisher assigns a DOI when your article is published and made available electronically. 

All DOI numbers begin with a 10 and contain a prefix and a suffix separated by a slash. The prefix is a unique number of four or more digits assigned to organizations; the suffix is assigned by the publisher and was designed to be flexible with publisher identification standards.

American Psychological Association.  (2013).  What is a digital object identifier, or DOI?.  Retrieved from

Where can you find the DOI for an article?

Usually the DOI can be found on the first page of the electronic journal article or if the article is found in a database, in the bibliographic record in the database.

If you don't see one and want to check, you can go to and type in the author's last name and the name of the journal article.

If a DOI is available, you will need to add it to your citation.

For example:

Karplus, M. (2010). Dynamical aspects of molecular recognition. Journal of Molecular Recognition, 23(2), 102-104. doi: 10.1002/jmr.1018

If the article does not have a DOI, then you would cite your article with the url of the journal home page.

If you found the article in a database and it is only published in that database, then you can add the database name and accession number or the database URL

For example:

Berman, R. P. (2009). Fused voices: Narrated monologue in jane austen's emma. Nineteenth-Century Literature, 64(1), 1-15. Retrieved from

Bilger, A.(2009). Women Novelists Before Jane Austen: The Critics and Their Canons (review). Tulsa Studies in Women's Literature 28(1), 201-202. The University of Tulsa. Retrieved October 9, 2013, from Project MUSE database.

For more information about APA Format, you can check out the APA Manual or the APA Style Blog.