"The end product of all your research is the paper that you complete for your class. An important component of your paper is the documentation that gives credit to the sources you used to write it. Without this documentation, you are essentially committing plagiarism. Citing your sources has three purposes:
To give credit where credit is due, thus avoiding any allegations of plagiarism
To enable any reader of your paper to locate the sources used in the paper
To give credibility to the facts you state in your paper
... The variety of documentation styles reflects the diversity and sheer amount of information available today and the specific needs that researchers in different fields have. ... No matter which style you have to use, the important thing is to be consistent."
Quaratiello, Arlene R. and Jane Devine. The College Student's Research Companion. 5th ed. New York: Neal-Schuman, 2011. Print.