Track sources and format bibliographies as well as download citations from library catalogs and databases.
Thomson Reuters EndNote X7 is a free download for GSU students, faculty and staff.
Zotero is a free application. It works well in FireFox, Chrome and Safari.
Check out this page for a comparison of several citation managers.
Zotero has many additional citation and journal styles available.
After you have all components of Zotero downloaded go to Zotero.org/styles. Type the name of the style you're looking for and click on it. You'll be asked to allow the style to install. Click the Install button. The style should be loaded as a choice.