The purpose of conducting research is to be able to participate in dialogue with other individuals within the same discipline, and demonstrate that you are a credible writer with extensive knowledge on your topic. When resorting to the ideas of others, it's crucial to cite these sources. Writers in different disciplines expect writing in that discipline to resort to a certain style for citing references.
Ask your instructor or check your course syllabus to find out which style guide to use. The following style guides are frequently used:
MLA Style is commonly used for literature, arts and humanities.
For more on MLA consult the AUC guidelines and handouts
APA Style is often used in psychology, education and other social sciences.
The following sites provide links to additional style guides that are frequently used, including Chicago, Harvard, Turabian, AMA and CBE:
Research and Documentation Online
(From Diana Hacker, Prince George's Community College)
Resources for Documenting Sources
(From Purdue University OWL)
Citing References in Your Paper
(From University of Wisconsin-Madison Writing Center)