[Libreoffice] flaw/bug cross reference

Hello,

I have a problem when using cross references. If I make a cross reference to
the number in a list it looks like this:

Birds can fly [2.]

It should look like:

Birds can fly [2]

It's just wrong to use dots after the number when referring to
your literature list. Libreoffice does that automatically and the dot is not
removable without removing the reference. Can you make so that the dot is
not included in the cross reference? Students handing in a paper with the
dots in the wrong places can get a lower grade...