SimpleXML - how to add <atom:link> tag?

[Mchl]

I'm working on making my news feed as valid as possible.

One of the W3C recommendations, is to add self reference tag, that look like this

<atom:link href="http://www.site.com/news.xml" rel="self" type="application/rss+xml" />

 

 

I'm trying to do this with SimpleXML, but so far no progress...

 

And after I create a tag like this, how do I add attributes?? (I tried loading an empty tag from string, and then adding attributes, but again nothing)