Kopernio can export .RIS files which are compatible with most reference managers like EndNote, Zotero and Mendeley.
You might have set up your reference manager as the default application to open all .RIS files, but if that's not the case just follow these steps:
1. Click on the [Export Reference] button when you are in the Kopernio PDF viewer.
2. Click the arrow icon on the download tile (or right-click the tile), select [Open With] and choose [Other].
3.A) Select your reference manager from the list of recommended applications and click [Open].
(You might want to tick the 'Always open with' box.)
3.B) If you use Firefox this step looks really similar:
Chrome users can import the full-text article with the reference and the same integration for Firefox is on our roadmap.