RefWorks is an online citation manager that can help you keep track of your references.
With RefWorks you can:
Getting started with RefWorks:
Mendeley is a citation management tool that helps you manage, share, read, annotate, and cite your research papers. It is also helps you manage your papers online, collaborate with other researchers, and discover research articles, trends and statistics.
With Mendeley you can:
Mendeley has both a desktop and an online component.