OWL -- The Online Writing Lab at Purdue University
The Writing Lab at Purdue University does a superb job of helping to guide students in the use of the writing style guides. Be sure and visit their site once you have put your own citations into the proper format to see check your work.
Popular Writing Style Guides
If you do not know which citation system you should be using--ASK YOUR INSTRUCTOR! Here are the most common ones.
This is a brief guide to the APA style manual with the most often cited kinds of sources. For the entire guide, visit the Reference Desk on the first floor of Waldo Library. The book's call number is: BF 76.7 .P83 (Reference Desk Collection).