Publication Manual of the American Psychological Association by 
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Citation tools allow you to save and organize your research. They also let you create formatted bibliographies.
Downloadable as a standalone program or a Firefox extension, Zotero is designed to store content in any format, including PDFs, images, audio and video files, and snapshots of web pages. Zotero operates with thousands of sites, and automatically indexes your library for ease of access.
A personal citation library designed to directly import references from multiple databases. In Refworks you can organize and manage your citations, share them with colleagues, and format bibliographies.
Downloadable as a standalone program from OIT, EndNote is a powerful citation tool for organizing your research and creating formatted citations. In addition to the standalone option, you can create an EndNote Web account.
