That doesn’t mean that you need to steer clear of this great resource, however. Don’t forget that if you scroll down to the bottom of whatever page you’re looking at, you’ll find all kinds of sources. You can often trace these sources back to where they came from, or just cite them in your paper directly when you choose to use Wikipedia as an academic writing source.
Let’s say that you’re talking about the morning of the battle. When you look at that section in Wikipedia, you’ll see that there are a few hyperlinked footnotes at the end of several paragraphs. The first three are numbered 19 to 21 and look like this:
19. Sears, p. 181.
20. Wolff, p. 60.
21. Sears, pp. 190–91.
You can find all the bibliographic information for those sources at the bottom of the page, and they’ll look like this.
Sears, Stephen W. Landscape Turned Red: The Battle of Antietam. Boston: Houghton Mifflin, 1983. ISBN 0-89919-172-X.
Wolff, Robert S. "The Antietam Campaign." In Encyclopedia of the American Civil War: A Political, Social, and Military History, edited by David S. Heidler and Jeanne T. Heidler. New York: W. W. Norton & Company, 2000. ISBN 0-393-04758-X.
McPherson, James M. Crossroads of Freedom: Antietam, The Battle That Changed the Course of the Civil War. New York: Oxford University Press, 2002.
Eicher, David J. The Longest Night: A Military History of the Civil War. New York: Simon & Schuster, 2001.
"Antietam”. Online Etymology Dictionary. http://www.etymonline.com/index.php?term=Antietam. Retrieved 4 Arpil 2011.
Pay particular attention that that last source, the one for the Online Etymology Dictionary. Notice that it lists the website, which is good, but it also lists the retrieval date. This is when the person who wrote the Wikipedia article on the Battle of Antietam accessed that site and got the information.
You should do two things with this before putting it in your paper. First, go to the link and see if the site is still up and providing information. In this case it is, so I’ll change the date from “4 April 2011” to whatever today is, in this case “21 March 2013.” Your professor might not have time to check all of those, but your TA might, although I highly doubt they will, unless you’re in a small class or the paper is quite serious.
“Battle of Antietam.” Wikipedia: The Free Encyclopedia. Wikimedia Foundation, Inc. 15 March 2013. Web. 21 March 2013. <http://en.wikipedia.org/wiki/Battle_of_Antietam>