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Citing Your Sources: Citing Basics


Why is Citing Sources Important?

  • To give credit to ideas that are not your own
  • To provide support for your argument
  • To enable your reader to find and read the sources you used
  • To avoid Honor Code infractions

What Needs to be Cited?

  • Exact wording taken from any source, including freely available websites
  • Paraphrases of passages
  • Indebtedness to another person for an idea
  • Use of another student's work
  • Use of your own previous work

You do not need to cite common knowledge.

What is Common Knowledge?

Widely-known, generally-accepted information that is not attributable to one source.


  • Thomas Jefferson was the third president of the United States. (common knowledge, no citation needed)
  • Thomas Jefferson was a slave owner. (common knowledge, no citation needed)
  • Thomas Jefferson owned 267 slaves in 1822.1 (not common knowledge, citation needed)

What is considered common knowledge can be tricky. When in doubt, ask your professor!

1. Cohen, William. "Thomas Jefferson and the Problem of Slavery." Journal of American History 56, no. 3 (1969): 503-26.

What's Involved in Citing Correctly?

In most citation styles, two parts are needed:

  1. An in-text citation
    Whenever you refer to the work of another person, you must indicate within the text where you got the information. The in-text citation provides a brief reference and points your reader to the complete citation.
  2. A list of works used
    The final page of your paper is usually a list of resources you cited or consulted.

Use the tabs above to learn about these two parts in your chosen citation style.

What Citation Style Should I Use?


  • ACS (American Chemical Society) for chemistry
  • APA (American Psychological Association) for psychology and other social sciences
  • Chicago (University of Chicago Press)
  • MLA (Modern Language Association) for literature, arts, and humanities