There are at least three reasons why writers cite their sources:
- To establish credibility with readers by calling on solid, reputable sources as "expert witnesses"
- To provide readers with the information they need to delve further into the topic
- To give credit where it's due and avoid plagiarism
When you are preparing a document,use this checklist to be sure your citaitons are complete.
- Did I provide a reference for every idea that came from a source? Cite all of your sources, even if you put the information in your own words. You do not have to cite sources for "common knowledge" - factual information that can be found in multiple sources such as dates or widely-known information.
- Do all of my in-text references have a complete citation in my list of sources and can the reader easily move from an in-text reference to the full citation in the list?
- Does my reader have all the information needed to find each source?
Because scholars in different disciplines emphasize different things when they read citations, there are many different styles. The MLA style, used for literary studies, makes sure page numbers are provided in an in-text citaiton because the exactness of a quotation matters; the APA style used in psychology and other social sciences include the year of publication, because when research was conducted is considered particularly significant. The Chicago Style is used by disciplines such as history and religion, which value sources so much it's common to put all the information about a source in a footnote as well as in a bibliography at the end of a paper.
Whatever style you use, citations typically include author, title of the work, and publication informaiton (for books, place, publisher, and year published; for articles, the journal, volume, date, and page numbers; for websites, a URL may be needed).