Two authenticators
Activate, use and manage the Google Authenticator app - The University of Auckland
RightSignature- Mandatory enforcement of Two-factor authentication
How to set up the Two-Step Authorization (Google Authenticator). – Gaijin Support
Two-factor authentication for your URIports account
How to use RoboForm as a 2FA authenticator for other sites and apps – RoboForm
Web Authentication: An API for accessing Public Key Credentials - Level 2
Two Factor Authentication (2FA) for Thinkific - miniOrange
The Definitive Guide to 2 Factor Authentication - by Arsen
Two-factor authentication explained: How to choose the right level of security for every account
Two-Factor Authentication (2FA) Explained, How to Set Up 2-Factor Authentication on Adafruit
Use Security Keys with the Traditional Duo Prompt - Guide to Two-Factor Authentication · Duo Security
Certified Authenticator Levels - FIDO Alliance
WebAuthn Readiness Checklist