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Citing sources: When and why should I cite?

When and how to cite (and avoid accidental plagiarism!)

Why should I cite?

old booksWhy cite? Here are four good reasons:

  1. It is the the right thing to do (giving credit to the person or organization who had the idea)
  2. It shows that you have read and understood what others think about your topic (you have consulted with experts)
  3. It helps you avoid plagiarism
  4. It helps people find the sources you used in case they want to read more about your topic

Image Source: "Old Book-Basking Ridge Historical Society" by William HoilesWikiMedia Commons. is licensed under CC BY 2.0

When do I cite?

Cite when you are paraphrasing, summarizing or quoting information that is not your own.

Are there situations when I don't have to cite?

Sometimes. You don't have to create citations for:

  • Common knowledge (example:  George H W Bush was the 41st president of the United States)
  • Famous quotes ("That's one small step for man; one giant leap for mankind")

If you are in doubt, be sure to ask your instructor or a librarian!

Avoiding plagiarism

Plagiarism includes, but is not limited to, the inclusion of someone else's words, ideas or data as one's own work. You must carefully indicate which parts of your paper or speech come from an outside source. Simply listing the sources you used at the end of your paper is not enough to avoid charges of plagiarism.

A research paper

When an instructor asks you to write a research paper or a researched speech, he or she means that the product should include your own ideas and opinions plus evidence from outside sources -- properly cited. 

A good research paper balances:

  • Your own opinions and ideas
  • Information from outside sources

graphic of scales, to illustrate balancing of one's own opinions and outside sources in a research paper

Why cite?

Click on the green arrow inside the box to listen to the tutorial, or see the full screen tutorial by clicking the link at the bottom.


Source: "Why you need to cite sources tutorial," Lane Community College, Cooperative Library Instruction Project

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