Get JQuery Ui Version

I already found out, how to get the JQuery Version:

http://jquery-howto.blogspot.com/2009/02/how-to-check-jquery-version.ht…

// Returns string Ex: "1.3.1"
$().jquery;

// Also returns string Ex: "1.3.1"
jQuery.fn.jquery;

But not, how to output the Version of JQuery ui.
So I would like to tell you how to reach this:

jQuery.ui.version