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Research Guides

Citing Sources: When should I use a citation?

An overview of tips, tools, and resources for all your citation needs

When should I use a citation?

A citation should be used when content that did not originate with you is used to support your writing.

Content includes:

  • words (quotations, phrases, sayings, etc.)
  • thoughts or ideas (summarizations and paraphrases)
  • audio or visual material (photos, videos, screencaptures, powerpoint slides, social media content, audio recordings, etc.)

Here are a few pages from Excelsior OWL's guide to writing process to get you started:

What you don't need to cite

No need to cite what is known as common knowledge.

But, what is common knowledge? Common knowledge includes information that someone can easily trace and find the answer to.  In an academic context, common knowledge will depend on the audience, but here are some examples to get you started:

  • There are 24 hours in a day.
  • The President of the United States can serve up to two terms in office, each term lasting four years.
  • The phone number for emergency services in the United States is 9-1-1

More examples of how to determine if something is common knowledge:

Pro Tip

When in doubt, cite -- You won’t be judged harshly for adding a citation when it isn’t needed.  However, skipping a citation (whether it’s an accident or not) could be considered plagiarism, which can have serious consequences.