From v11.5.0, Zotero is a popular (free) reference manager. It can be used online or via a native macOS client. See: https://www.zotero.org.
Zotero integration requires a Zotero ID and Key. These are not available if only using the macOS Desktop client app and can only be obtained by (creating a free account and) logging into Zotero on the Web, then visiting the account’s Security page, https://www.zotero.org/settings/security . The ZoteroID is a seven-digit account number.
The menu Edit ▸ Insert has three Zotero-related options (see explanations):
- Lookup in Zotero (⌘⇧-Y).
- Zotero Scan.
- Zotero Unscan.
See also—notes linking to here: