A quick note in the text of your paper anytime you use an existing source of information. The "in-text citations" tab to the left shows you how to include a note in the text of your paper when you use a source.
A complete list of the sources you used appears at the end of your paper. The tabs to the left will show you how to format citations of many different sources in your list of references. General guidelines on how you present a your list of references include:
Reference list starts on a new page. Type the word "References" centered at the top of the page.
Double-space all reference list entries
The first line of each reference is set at the left margin and subsequent lines are indented
Arrange alphabetically, not by format (book, journal, etc)