A reference is a direct link to a specific resource on a specific site. It also has an editable field to describe the resource.
One more set of points clarified: flagged links v in-line links - references. Clicking on the flag v clicking on the link text.
Added a comment to the discussion on my local fork of Opinionated Wiki. Interested to see if it gets forked back to fedwiki. It might not be seen on sfw.mcmorgan.org. If it doesn't I guess I could add my comment to the fedwiki version.