It is important to cite so that readers of your work know which ideas in your paper are yours and which come from someone else. Citations are an organized way of giving readers information about the sources you used. Complete and accurate citations help you avoid accidental plagiarism.
Citations go both ways. You can look at the citations in a book or article to find the sources that writer used. This can be a good way to find more sources on a topic you are researching.
Check with your instructor to see which citation style you should use for your class.
Cite any information that you quote or paraphrase, whether it is:
If the idea isn't yours, cite it!
You do not need to cite "common knowledge," that is, generally known facts. Example: George Washington was the first president of the United States.
These handouts can give you information and examples of citations. You can also find them on the Research Tools page of the library website.
The library has style manuals that will help you cite your sources correctly, both in the text of your paper and in your list of Works Cited or References. These manuals will also guide you in formatting your document according to the standards of the particular style.
Publication Manual (OFFICIAL) 7th Edition of the American Psychological Association by 
The Chicago Manual of Style, 17th Edition by 