I want to achieve a formatting like this:

Some text which references (1), for example because (1) might be an example sentence for some grammatical structure which is explained here.

This is auto-numbered text object 1.                                                                                      (1)
The number on the right is assigned automatically. If another auto-numbered object
is inserted before this, it will change to (2), as will all references in the surrounding text.

Some more surrounding text.

How can I insert such numbered sentences and references to them in LibreOffice 3.5.1?