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Citing Sources

A guide for source citation (APA, MLA, and Chicago)

Background Information

Citations perform very important roles in research, both at an academic and a professional level.

  • They tell your readers where you located your information.
  • They tell your professors what kind of research you performed.
  • They connect your research to the work of other researchers and scholars.
  • They give you authority as a writer and researcher.

Why Should I Cite?

Citing your sources

  • provides credit to the original authors,
  • prevents plagiarism, and
  • meets requirements of assignments.

When Should I Cite?

You should use citations whenever you quote, paraphrase, or summarize someone else's work.

  • Quotations are exact duplicates of other people's words.
  • Paraphrases are other people's ideas rewritten in your own words. They're usually about the same length as the original material.
  • Summaries are other people's ideas that you've shortened to highlight the main ideas. They're always shorter than the original material.

You should cite your sources whenever you write ideas that aren't your original ideas. For specific situations, take a look at: Plagiarism Resources.

"I've heard some people say citation, and other people say reference. What's the difference?"

Citations and references are linked to each other. When you cite a source, you're providing credit for that source in two different places: a citation and a reference.

  • The citation is placed within the text where you refer to the source. (It's also called an "in-text citation" for this reason.) This is a short version of information about the source. It could be a parenthetical citation: (Bradbury, 1970). Or, it could be an endnote or a footnote: 2.
  • The reference is placed in the list at the end of your paper. This is the longer version of information about the source, and it looks something like this:
    Bradbury, R. (1970). Fahrenheit 451. New York, NY: Ballantine Books.

The citation should always match the reference. That way, if a reader wants to find more information about a source while reading your work, s/he can just flip to the back to locate the source in your reference list according to the information you provided in your citation.

It's also a good idea to double-check that all of the sources in the in-text citations are in the reference list, and vice versa. In other words, don't include sources in your reference list that you didn't quote or paraphrase; that's called "bib padding."

Difference subjects/disciplines tend to favor specific style guides.

  • APA Style: social sciences, including psychology, sociology, and business, and some sciences
  • MLA Style: humanities, English, literature
  • Chicago Style: history, humanities

IMPORTANT NOTE: Check your syllabus and assignment instructions to see if your professor requires a particular citation style. Your professors' preferences will always be a higher priority that these general disciplinary categories.

Putting the Pieces Together

While there are different citation styles (APA, MLA, Chicago, etc.), they all serve the same purpose. And they all have similar fill-in-the-blank properties. Think of them like jigsaw puzzles. You just have to put the pieces together. And just as different jigsaw puzzles are completed in different ways, different citations have different orders of placement.

book citation jigsaw puzzle
citation jigsaw puzzle solved

book citation jigsaw scatter

citation jigsaw puzzle pile

Also, syntax and punctuation matter in the creation of citations. If you place the citation elements in the wrong order with incorrect punctuation, the citation won't work — just as the jigsaw pieces wouldn't fit together if the shapes or edges weren't exact matches.

All references provide the same types of information:

  • Who. Who's responsible for writing the source? Author, editor, translator.
  • When. When was the source published or produced? Date. Sometimes just year; sometimes month and year; sometimes day, month, and year.
  • What. What's the name of the source? Book, article, or journal title; series title; subtitle; etc.
  • Where. Who produced the source and where are they located? Publisher, publisher location, website URL or DOI, etc. Is the source from a specific location? Book chapter, edition, journal volume and issue number, etc.
  • Some citation and reference styles want to know the source's format, such as print or web, as well as when you accessed the material.

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