A citation informs a reader that the material in your work, such as a quote, image or idea, came from another source.
Research and scholarship is built upon the work of earlier scholars. By citing, you acknowledge the work of those earlier scholars and provide a pathway to their work, which allows readers to find your sources and consider the derivation of your ideas. Citations establish your credibility as a serious scholar by providing evidence that you have considered the existing information on a topic.
Failure to cite, or citing improperly, is considered plagiarism.
When do I cite?
You need to cite your sources whenever you quote, paraphrase or summarize ideas that are not your own, or make specific reference to the work of another.
You do not need to cite well-known, undisputed facts. It is not necessary to cite your own ideas expressed elsewhere in the same paper.
What do I cite?
Cite the source that you used. In other words, cite only what you have seen. To cite a work that you have not seen is dishonest and inaccurate. Ideally, you should always try to view primary sources because other authors may have misrepresented statistics, ideas or meaning from the primary source.