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Citation Help

Addresses how to cite sources, use sources, and avoid plagiarism.


What is a citation?

The act of telling your reader where you got your information is called citing your source.

The information you share when you cite a source is called a citation, or sometimes a reference.

When should I cite a source?

When you include information from a source in a paper, presentation, or other project, you must give credit to the source's author. (You do not have to cite information that is common knowledge, such as that the U.S. has 50 states.)

What is a citation style?

Different disciplines use slightly different formats for their citations. For example, scholars who write about literature usually use MLA style, while psychologists and other social scientists use APA style, and historians usually use Chicago style. 

This guide covers APA, Chicago, and MLA style. For information about other styles, visit Purdue Online Writing Lab | Research and Citation.


Direct Quote

  • Someone else's exact words, placed in quotation marks. and followed by a parenthetical citation.


  • Someone else's ideas explained in your own words, followed by a parenthetical citation.


  • Similar to a paraphrase, but used to give an overview of many ideas as explained in your own words.

Source material

  • A direct quote, paraphrase, or summary with proper citation.

Your writing is what matters most!

If your paper is a chocolate chip cookie, the source material (quotes, paraphrases) are like the chocolate chips, and your own original writing is the cookie dough.

Your writing is what holds everything together! In your writing, you might analyze the source material, relate it to your own ideas, critique it, use it as evidence to back up a claim, or refer to it as an example of a broader idea.

Your writing is what gives the source material context and meaning for your reader. If you just drop in quotes and paraphrases, that's like tossing someone a handful of chocolate chips when they asked for a great cookie.

Always properly cite an author's original idea, regardless of whether you have directly quoted or paraphrased it.

Types of Citation

The Two Kinds of Citation

There are two kinds of citation.

  1. A short little tag that appears in the main text of the article, essay, or book ("in-text").
  2. A much more detailed citation that comes in a list at the end of the article, essay, or book (called a "reference list" or "works cited list" or "bibliography") .

Readers look at the short in-text citation and then if they want more information, they look up the rest of the information in the long list at the end.  

In-text citations

These are short so that they don't interrupt the flow of reading. The exact rules vary according to citation style, but the in-text citation typically contains the author's name and the date of publication, sometimes with a page number.

Sometimes it is just a number - when it is a number, it is called a footnote or endnote number.

Example of In-text Citation in APA style, 7th Edition

According to Smith (2015), NYC pizza was ranked the most foldable kind of pizza by 999 pizza-eaters.

As a reader, you would now have enough information from this in-text citation to look at my list of references to find more information about where Smith provided this information in 2015 - it could be a book, article, video, interview, or any other source.

Reference List Citations

The matching end-of-work citation would be a reference list citation.

Example of Reference List Citation in APA style, 7th Edition

Smith, B. (2015). Survey of pizza-folders and their preferences. Journal of Pizzaology, 2(6), 16-20.

This longer citation provides the following information:

  • Author: B. Smith
  • Date of publication: 2015
  • Title of article: Survey of pizza-folders and their preferences
  • Title of journal where the article was published: Journal of Pizzaology
  • Volume of the journal: 2 (Journals usually publish one volume per year, so 2015 was probably the second year that this journal existed)
  • Issue: 6 (This would probably be the 6th issue that was published that year)
  • Page numbers: 16-20