added source for further configuration

README.md

@@ -40,3 +40,4 @@ Mainly influenced by the implementation/example of
 - https://fedoraproject.org/wiki/Fail2ban_with_FirewallD
 - https://computingforgeeks.com/install-and-use-firewalld-on-ubuntu-18-04-ubuntu-16-04
 - https://www.digitalocean.com/community/tutorials/how-to-protect-an-nginx-server-with-fail2ban-on-ubuntu-14-04
+- https://snippets.aktagon.com/snippets/554-how-to-secure-an-nginx-server-with-fail2ban