Try Similar SitesZotero Connector: Best for researchZotero is one of the most widely used free tools to manage citations. The Zotero Connector not only lets you link to an installed edition of Zotero on Windows, macOS or Linux, but it can also store citations to Zotero.org online. While Zotero.org and the extension are free, you may choose to pay for storage if you need to preserve more than 300 megabytes of papers and links online.