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Citation Styles

Learn how to cite articles, books, reports, theses, legal documents, and more using citation styles like APA, Chicago, and IEEE.

Cite Responsibly, Avoid Plagiarism

Citations are needed to:

  • validate information
  • give credit where credit is due
  • allow other researchers to follow in your footsteps. Your readers should be able to tell where they can go for follow-up information regarding any claims, data, or facts discussed in your writing—whether it be to you, the author, or to specific works from which you gathered pertinent information you have incorporated into your text.

You may want to ask yourself the following as you write and review:

  • Do I know this information/term/data because I read it somewhere?
  • Is this knowledge the result of emails or conversations? (Unpublished information still must be cited in the text.)
  • Is this my own analysis based on my personal knowledge set and/or research, or is it analysis I borrowed from another person?
Your own experience and findings, and common knowledge, do not need to be cited.
Common knowledge is usually considered something your reader already knows. As a rule of thumb, if you can find an unattributed fact in five credible sources, a citation is not needed (for example, “The average adult body contains about 250 grams of salt” or “George W. Bush served as president of the United States from 2000 to 2008”). Common knowledge also includes field-specific knowledge, so it, too, doesn’t need to be cited. Consult a faculty member from your department or your library liaison if you are unsure if something is field-specific common knowledge.
A citation or a signal phrase is needed with every sentence that uses a source’s idea, statistic, or wording.
It must be reasonably clear to the reader which pieces of information came from which sources, and which are your original thoughts and data.
One citation at the end of a paragraph cannot “cover” an entire paragraph.
Cite the source completely the first time it is used in each paragraph. Then, throughout the paragraph, make it reasonably clear that information was gathered from the same source already mentioned. Cite the source again just before your focus moves to another source.
Make sure you are differentiating between information that is paraphrased and information that is directly quoted.
Generally, a phrase that contains five or more consecutive words exactly as they appear in the source should be in quotation marks (proper nouns excluded) or paraphrased. Please remember: Both types of information require citations.
Try to limit direct quotations to information that you are unable to paraphrase adequately.
While quoting can be effective (and sometimes essential for important, precise wording), relying on too many direct quotes—especially block quotations—does not demonstrate your understanding of the topic or your ability to think critically about others’ work. There are exceptions, but, in general, not more than 10 percent of your document should be quoted from others.

The Graduate Writing Center is here to help with draft papers.
Writing coaches can help you build up your paraphrasing, quoting, and citation skills. You may also request to have a draft paper run through NPS’ plagiarism detection software, Turnitin; a writing coach will meet with you to help determine problem areas and guide your revisions.

Required Citation Styles

Other Relevant Guides

RefWorks 3

RefWorks 3 is a web based citation management tool that you can access from any internet connected computer.

If you are new to RefWorks, please sign up for the new RefWorks 3

If you are an existing user of RefWorks 2.0 ("Legacy RefWorks") login to RefWorks 2.0

You can:

  • Add citations from Library databases, the web, or manually
  • Organize your citations into folders
  • Annotate your citations with personal notes
  • Add citations and reference lists, formatted in any style, into MS Word

Library Staff Contacts

DKL staff contacts

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411 Dyer Rd. Bldg. 339
Monterey, CA 93943


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