gtk tree view tutorial

I found the http://scentric.net/tutorial/treeview-tutorial.html very useful and would like to add it to the wiki but couldn't find the right place for it. My first guess was "Resources", but then it says in the first sentence "resources related to PHP-GTK". I couldn't find anything which is gtk+ only but I think that if you work with php-gtk you can't avoid the facts you're working with gtk+ and thus linking to such tutorial this would be a benefit. What do others think? - Markus