getResourceBundles().add css or javascript in wicket application

Dear forum,
I want to bundle css files from inside my wicket application.

I read wicket guide Resource management
<https://wicket.apache.org/guide/guide/resources.html> chapter and wicket
in action Wicket 6 resource management
<http://wicketinaction.com/2012/07/wicket-6-resource-management/> blog.

The examples provided refer to static files that one packages with one's
project.

Is it possible to reference to remote css or java script files, like Font
Awesome
<http://maxcdn.bootstrapcdn.com/font-awesome/4.1.0/css/font-awesome.min.css>
, for example?

Also, what is the recommended practice? To download third party css and
javascript files and bundle them in the application or to reference to them
via URL?

Thanks in advance,
Lucas