Click in the spot in the document where the in-text citation should go.
Click on the Zotero tab at the top.
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The Zotero menu will appear.
Click on Add/edit citation.
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Choose your citation style and click OK.
Search your Zotero library by keyword in the box that appears.
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Or click on the Zotero icon in the search box to switch to Classic View.
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You can now browse your Zotero library.
Click on the correct item for your in-text citation and click OK.
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The in-text citation, in proper format, is inserted into your Google document.