Google Online Security Blog: Google Authenticator now supports

How to Add Two Factor Authentication (2FA) in WordPress to Enhance Your Site Security - WPvivid

Bypassing Google's Two-Factor Authentication - Duo Blog

Google Authenticator - Apps on Google Play

Google Authenticator will now sync your 2FA codes to use on different devices

How to Backup Google Authenticator or Transfer It to a New Phone

Google Authenticator vs Protectimus SMART Authenticator App

What is Google Authenticator?

Two Factor Authentication (WordPress 2FA) plugin for Login - WP 2FA

What Are Authenticator Apps and How Do They Work? – Keeper