Even if the information is not new to you, butwould be unfamiliarto the readers of your paper, then cite the information. Two common ways of showing the source of material are footnotes andendnotes. Footnotes and endnotes are cool. Think of them as hypertext linksbefore computers. Take a look at a law journal article someday.
Lawyers go nuts over footnotes.
I won't go into a discussion about which method to useor all the technical details about citation forms. Do not rely on thispage for how to reference works. Ask your instructorwhich method is preferred and how to do it. This is a rule that often causes trouble. It takes work to put someoneelse's ideas into your own words.