One purpose of documentation is to acknowledge the sources used. The Works Cited page of a research paper provides the information required in order for the reader to find an exact copy of each of the original sources used by the researcher. An internal citation appears at the place within the paper where the writer used the quote, summary, paraphrase, or idea; points back to the source on the Works Cited page which is being used; and tells where in that source to find the information, ideas, or words used. Think of the internal citation as a license tag, giving the writer permission to use someone else's words, information,or ideas. In MLA, the format of a citation is usually the author's last name and a page number. If the source does not list an author, the title of the source is used.
For electronic sources, like web pages or full text article reprints, page numbers are not used since each person printing the article could end up with different page breaks. In those cases, sometimes paragraph numbers are used. To differentiate paragraph numbers from page numbers, paragraph numbers are preceded by the abbreviation par. So, if page 7 is used from a source by someone named Martin, the internal citation (also called "parenthetical documentation") would be (Martin 7). If paragraph 12 is used from a web site titled George Washington Carver, Botanist that does not list an author, the internal citation (also called "parenthetical documentation") would be (George Washington Carver, Botanist, par. 12). For the sake of simplicity, we can refer to the internal citation or parenthetical documentation as a tag.
Writers must remember that everything (absolutely everything) in their papers must be clearly indicated as their own idea or someone else's. Anything that is not an original idea of the writer's must have a source, and that source must be cited (tagged). If students are writing about topics where they might be considered authorities (for instance, a practicing midwife writing about the Lamaze childbirth method), students should indicate their status as an authority early in their paper.
Best Practice: Good students include the tag in their notes. Failing to include citations (tags) in notes makes it easy to plagiarize.
ENGL1010 Composition I