inside the car? They are covered with headliner material. But this material has no foam underneath, whereas the haedliner material under the 'real' headliner has a 3 mm foam in between. That foam gets very old over time and is like a kind of soft glue and the headliner comes down.
Maybe you have a look at my page under headliner repair. There are a lot of pics too and a very detailed instruction how to do. I did that about 3 months ago.
Hope that helps.