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Online Writing Lab

Citing Sources

Once a source is found and incorporated into an essay, the source needs to be cited. The information that must be included to cite a source depends on the format (MLA, APA, Chicago Manual of Style) that is being used for the essay. However, regardless of format, the purpose of all citations is the same: to avoid plagiarism and to provide the reader with the necessary information about where the information originates from. 

Many beginning writers think of plagiarism as trying to pass off information or words (writing) from someone else as the writer’s own. While this is true, plagiarism also occurs when outside information that is used in an essay is not cited correctly or cited at all, regardless of intent. The consequences of plagiarism can be quite severe and can range from flunking an individual assignment or class to facing possible expulsion and sometimes even legal consequences. Because of this fact, all writers need to learn how to cite sources properly. 

What to cite
Most writers know that quotes (using someone else’s exact words) must be cited; however, quotes are not the only type of information that needs to be cited in an essay. Any information that is taken from another source, even if it is paraphrased (put into different words), needs to be cited in the same manner as a quote. In other words, claims and ideas that originate from others need to be cited as well. As mentioned earlier, the proper way to cite a source depends on the type of source and the format that is being used for a paper, but regardless of which format is used, the most important aspect of citing any source is making it clear that the information being presented is coming from another source by giving the full name of the author or person behind the information that is being used. 

Here is a list of information that should always be cited:

Quotes: Anytime the exact wording of an original source/author is used, no matter how short or long the wording is, it must be placed in quotation marks and attributed to the original source. This is also true of partial quotes (when only part of a sentence, for example, is used)

Paraphrases: A paraphrase involves restating original information into new language. The key to a successful paraphrase is to change both the wording used and the order, or structure, or the sentence. Unless the original language is vivid and/or original and changing it would result in a loss of meaning, paraphrasing is generally preferred to quoting. Paraphrases must be cited by attributing to the original source just like quotes. 

View the Paraphrasing Page and the Using Quotations page for more information.

Statistics and other data: The results of studies often result in statistics. This type of data must be cited by providing the name of the person or agency responsible for generating the statistic(s). The use of statistics and other data is common is research essays.

Studies: The findings and/or interpretations of studies must be attributed by citing the primary researcher(s) responsible for performing the study. If using a secondary source that interprets a study done by someone else, that source must also be cited.

View the Primary vs. Secondary Sources Page for more information.

Arguments and ideas: Anytime you, as the writer, are providing or furthering a specific argument made by someone else, this needs to be cited. The same is true of original ideas. 

Summaries: A summary is a condensed version of another work put into your own words. In this sense, it’s like a paraphrase, but summaries generally occur when using longer or complete sources. For example, a writer may summarize an entire essay or study, a section or chapter of a book, or even an entire book. When summarizing, be sure to cite all information to the original author by using author ID tags and cite specific information (such as stats) or quotes with full citations. 

View the Summarizing Page for more information.

When in doubt, cite. Following this general rule will eliminate plagiarism. At worst, it will create an unnecessary reference/citation in the text, but an unnecessary citation is much better than a missing one.

Common Knowledge

Some facts and dates do not have to be cited because they can be found numerous places and, thus, are not attributable to one particular source. This is referred to as common knowledge, not because everyone knows this information offhand, but enough people do that the information is considered common (hence the term common knowledge). Examples of common knowledge include widely known facts and dates. For example, if a writer wanted to mention that the United States’ Declaration of Independence was ratified on July 4, 1776, this information is considered common knowledge and would not have to be cited, even if the writer had to look up the exact date to be sure.  

Again, though, always follow this general rule: when in doubt, cite.

For more information on citing sources correctly, view the MLA, APA, and Chicago Manual of Style and examples located on this site, use a credible reference manual, and/or visit the Aims Learning Commons and speak with a librarian or writing tutor.