Cite right : a quick guide to citation styles--MLA, APA, Chicago, the sciences, professions, and more by 
Publication manual of the American Psychological Association by Zotero [zoh-TAIR-oh] is a free bibliographic manager that is usable with the Firefox web browser tool which allows you to collect, organize, manage, and cite your sources in your browser.
It is now available in a standalone version to use also with other web browsers.
Zotero helps you do the following:
Zotero is freely available for download at http://www.zotero.org/.
Additional information: Zotero Tutorials
