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When and Why to Cite Sources

When and Why to Cite Sources

What is Plagiarism?

Plagiarism is defined as "a piece of writing that has been copied from someone else and is presented as being your own work" or "taking someone's words or ideas as if they were your own" [1]

Plagiarism is a serious issue in the academic community. While plagiarism sometimes does occur intentionally, it also occurs because the writer doesn’t understand or does not know how to avoid it. Please visit our online tutorial: Plagiarism 101 for an entertaining and interesting look at why people plagiarize and strategies to avoid it.

Plagiarism occurs when you use someone else’s ideas and PRETEND they are your own. Avoiding plagiarism doesn’t mean that you can never use other people’s ideas. It’s a widely known secret that in fact you CAN use other peoples’ ideas and even their words. For many research papers you NEED to do this in order to prove your own points. So use their ideas! Use their words! Professors expect to see in your writing that you’ve done your research and understand what the experts think when you formed your own opinions. The trick is to acknowledge who these expert ideas really belong to by CITING them!

So let’s assume you don’t want to plagiarize, you’ve given yourself enough time to do it right, but you’re still not sure about “putting things in your own words,” judging when to cite work, or how to cite it. Read on for more information and examples.

Why Acknowledge Sources

Doing research for a paper is an exploration and learning process. By acknowledging our sources we show our reader the path we took to come to our conclusions. Citing the authors we read shows how we tied others’ research and ideas together and how we came to learn about and develop our own ideas and opinions.

Why should you cite your sources?
  1. Citations reflect the careful and thorough work you have put into locating and exploring your sources.
  2. Citations help readers understand the context of your argument and are a courtesy to the reader, who may share your interest in a particular area of study.
  3. Citations allow you to acknowledge those authors who contributed to your learning and your work.
  4. Citations, by illustrating your own learning process, also draw attention to the originality and legitimacy of your own ideas.
  5. By citing sources you demonstrate your integrity and skill as a responsible student and participant in your field of study. [2]

When to Cite Sources

While professors and scholars may have specific requirements based on the needs of their discipline, there are cases where you should always cite your sources.

  1. Direct quotes of more than one word. If the author’s words are powerful or you need to be specific for your argument, the authors’ words can be used as a direct quote.
  2. Paraphrasing or summarizing. If you want to use someone else’s idea to help you make your point or to support your own ideas, in this case you would “translate” the ideas into your own words.
  3. Information which may be common knowledge but still unfamiliar to your reader. This would also include statistical information which may be familiar information but still requires confirmation.
  4. Not just books or articles should be cited. Any source that you use for information can and should be cited including interviews, websites, TV programs, etc.
  5. Whenever you are not sure if something should be cited, err on the side of caution and cite sources.

Let’s look at some examples…

Direct quotes

How much you quote will determine how it appears in the body of your paper but whether it is one word or an entire paragraph, direct quotes need to be cited.

Lappe’s explanation of a "thin democracy" [3] addresses a number of basic flaws within our American society.

Global warming is being recognized as a major issue throughout the world and as Al Gore instructs, "it is time to make peace with our planet." [4]

Paraphrasing or Summarizing

This involves translating what you have read (or heard) and putting it into your own words. Paraphrasing typically refers to putting an idea or passage into your own words. Summarizing involves capturing the main idea or reducing a detailed piece to a shorter and more general synopsis.


"Instructors usually allow students to find their own topics for a major writing assignment; thus choose something of interest to you so you won’t get bored after a few days. At the same time, your chosen topic will need a scholarly perspective."[5]

Paraphrase: When students are permitted to select their own topic to write about they should choose one that is interesting to them. The topic should also be scholarly in nature so that students will be able to find appropriate research and resources on the topic. [5]

Summary: Students should select writing topics that are interesting and also lend themselves to academic research. [5]

A summary generally addresses the overall theme of a passage, article, opinion, etc. while a paraphrase generally restates a more specific thought or idea. The difference between summarizing and paraphrasing is sometimes obvious and sometimes subtle — do you see the difference?

Common Knowledge? Or Not?

Some basic facts are common knowledge and easily confirmed from a variety of sources. Statistics should always be cited, as well as opinions and less familiar facts. Information that is considered well-known within your field of study will also help determine if it is considered common or not. However, if you are not sure, cite it!

Example 1:

The University at Albany located in Albany, New York and is part of the State University of New York.

This is common knowledge and easily confirmed in a multitude of sources.

Example 2:

The State University of New York was officially established in February of 1948 and currently consists of 64 institutions. The University at Albany is one of ten University Centers that are part of the SUNY system. [6]

While the SUNY system is well known and these facts are easily confirmed, specific historical information or statistics should be cited.

How to Cite?

We’ve talked about plagiarism as well as why and when to cite. The next question is "How?"

There are two things you need to know from your professor.

The FIRST is how you will reference your sources within your paper. Generally you will use one of the following options:

  • IN TEXT citation is when your source author is included within the body of your paper. This acts as a reference to your 'Works Cited' page.
  • END NOTES format is used in this document. The cited idea or quote is noted with a number and the source is listed at the end of the paper.
  • FOOT NOTES format is similar to end notes however the citations are listed at the bottom of each page.

The SECOND thing you need to know is what Format and Style Guide to use. There are very specific rules about how to do this that are not included in this document. Your professor will tell you which s/he wants you to follow. The choices will typically be one of the following:

  • MLA Format and Style Guide (Modern Language Association)
  • APA Format and Style Guide (American Psychological Association)
  • CHICAGO Manual of Style

Please visit the University Libraries' Cite... Web page at Cite... for information and instructions on these style guides. Once you know what your professor wants you will need to follow the rules of that format accordingly.

[1] "Plagiarism." WordNet 3.0. Princeton University. 03 Apr. 2008.

[2]Adapted from "Sources and Citation at Dartmouth College." Dartmouth College. 1998. Retrieved 9 Feb 2009.

[3]Lappe, Frances Moore. Getting a Grip. Cambridge, MA : Small Planet Media, 2007.

[4]Gore, Al. "Nobel Prize Acceptance Speech." Al’s Journal. December 10, 2007. Retrieved April 10, 2008

[5]Lester, James D. & James D. Lester Jr. Writing Research Papers: A Complete Guide, 11th Ed. New York: Pearson Education, 2005.

[6]"Short History of SUNY." The State University of New York. 2008. Retrieved April 25, 2008.

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