BK Writing Lab

When to Cite Your Sources
Paul DiGeorgio, Ph.D.


You must cite your sources when…

1. You directly quote at least two words exactly as they appear in the source, or one word if it is used in an unusual/innovative way.

2. You indirectly quote a source, meaning that you paraphrase.

3. You summarize a source.

4. You provide facts or data from a source.

5. You copy the structure of the argument in a source. Even if you are using your own wording, copying someone’s argument without citing them is plagiarism.

6. You expand upon the work or method of someone else.

7. You modify code or mathematics.

8. You collaborate with others.

9. You use an image under copyright, or someone’s video or audio.

Be careful that you do not cite too much. Most preparatory schools and universities/colleges will use plagiarism software that will tell your instructor how much of your paper is quoted material. As a general rule you should try to avoid quoting any more than 20-30% of your total paper length. Sometimes students turn in papers that have more than 50% quoted material -- in these cases you are turning in mostly someone else's work!

You do not need to cite when something is "common knowledge." For more information check here


If you have any questions, send us an email at bkwritinglab@bishopkennyhs.org!


Image Credit: Source by Gregor Cresnar from the Noun Project

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