Zotero: Open source reference management software
Compatibility: Mac and Windows
Current version: 5.0
Integrates with Microsoft Word using Zotero Bibliographic Management. Will also work with Google Docs, OpenOffice and LibreOffice. The latter two are open-source office suites similar to Microsoft Office.
Zotero is free to most users. You can purchase additional storage space if needed ($20/yr for 2 GB).
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