diff --git a/docs/admin/configuration/mail-notifications.md b/docs/admin/configuration/mail-notifications.md
index f813fc81..abbc7461 100644
--- a/docs/admin/configuration/mail-notifications.md
+++ b/docs/admin/configuration/mail-notifications.md
@@ -35,8 +35,11 @@ SMTP_USERNAME=YOUR_USERNAME
 SMTP_PASSWORD=YOUR_PASSWORD
 SMTP_TRANSPORT_ENCRYPTION=none
 SMTP_INSECURE=true
+SMTP_AUTHENTICATION=auto
 ```
 
+See section [Environment Variables](https://docs.opencloud.eu/docs/dev/server/Services/notifications/notifications-envvars/) in the developers documentation for possible values for these variables. Note, that the environment variables are prefixed with `NOTIFICATIONS_`, so `NOTIFICATIONS_SMTP_AUTHENTICATION` shows possible values for `SMTP_AUTHENTICATION` in the `.env` file.
+
 Per default the `notifications` service is disabled. To send out notifications, the service must be enabled via:
 
 ```env