Citation Guide

Help & FAQs


What is a DOI (Digital Object Identifier)?
A DOI is a unique alphanumeric string that identifies articles, ebooks, standards, datasets, etc. and provides a persistent link to their online location.

Why use DOIs?

  • They make citing easier for you and finding references easier for your reader.
  • You can put a DOI into a Web search and find the item it's linked to.
  • If you cite something you got from a subscription database, you don't need to worry about including the URL to the journal: just add the DOI string as formatted above.

Try it!

Paste this DOI into your browser search bar: 10.1080/10242690701505419   

Did you retrieve this article?

Sanico, Grace F., and Makoto Kakinaka. “Terrorism and Deterrence Policy with Transnational Support.” Defence and Peace Economics 19, no. 2 (April 2008): 153–67.

A properly formatted DOI link should look like this:

DOI Search Tool
Use the Crossref Lookup Tool when you have the DOI or the citation.

Our Citation Tools guide will help you decide which type of tool best suits your needs. Quick citation generators will create single citations on the fly, while more robust citation management software allows you to organize and format your references and insert citations into your Word document using an integrated plugin.

Citation management tools such as Zotero and Endnote are useful when citing in your theses and papers; they typically generate citations that are 80–90 percent correct. However, you'll still need to proofread and manually edit your citations as needed. It's best practice to check your formatting against the examples and rules provided in this guide.

Which tool to use is your preference, but many of our students are finding Zotero to be easy to learn and use. It is open-source and has been around for quite a while, so the documentation and community resources are well developed and available in a number of languages.

We recommend NOT using RefWorks or the References function within Microsoft Word.

Each citation style has rules specific to that style. Applying the rules to the examples can help you format your citations properly. We provide essential rules for the most commonly asked questions.

Some examples:

  • The difference between Title Case and Sentence case
  • The difference between a Bibliography and a List of References
  • When to use italics or quotation marks
It depends on the professor! If your professor does not require a specific citation style for class papers, we suggest that you practice using your department’s or advisor’s chosen thesis citation style; practice should make formatting and citing less daunting during the thesis-writing process.
We review thesis citations with the following aims, in order of importance: 1) to minimize the risk of plagiarism; 2) to provide complete source information; 3) to comply with citation style rules; and 4) to demonstrate consistent citation formatting throughout your document.

See the TPO Citation Guides page with links to:

  • Video on plagiarism (5:27)
  • How to cite responsibly—must reads
  • Workshops
    • "Paraphrasing and Quoting Like a Pro" provides tips, techniques, and practice on paraphrasing, quoting, and summarizing sources.
    • "Citation Management with Zotero" will help you get started with collecting, managing, and formatting your citations.

Get expert personalized advice

Both the GWC and TPO are happy to help you with your citations.



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Help with research; search strategies; finding books, articles, reports on a topic; finding NPS theses; citations & Zotero; library accounts and access