BibDesk is a free LaTeX-compatible Mac bibliography manager app BibTex front-end.
Hookmark enables you to link BibDesk entries to and from anything that is also linkable. This integration is courtesy of Christiaan Hofman, provided in a Bibdesk SourceForge thread. Christiaan Hofman is the Skim PDF Mac app developer.
This has many advantages over EndNote, Mendeley and Papers app.
More info coming soon. 2021-03-11.