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Zotero offers plugins for programs like Microsoft Word, Google Docs, and LibreOffice. The plugin adds a Zotero toolbar that allows you to add citations to your document while you write. The Microsoft Word toolbar is in the top menu after 'View' and has five buttons:
The plugin is included in Microsoft Word and LibreOffice automatically when you download Zotero Standalone. If you don't see the Zotero toolbar when you open your word processor:

See Zotero's documentation on word processor plugins for detailed information.
Part or all of this answer is adapted from Zotero wiki content distributed under various Creative Commons licenses. Additional content may have been adapted from the Zotero Research Guide by Jason Puckett and licensed by Georgia State University Library under a Creative Commons Attribution-Noncommercial License.
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