In order to use most of the special collections, you need to contact the library. The library staff will bring the materials from the closed stacks to the Renvall Reading Room in the Feeniks Library.
The easiest way to contact the library is by sending an email to email@example.com.
If the materials you want to use is included in the library catalogue, you should try to describe what you need and/or your research questions as precisely as you can; most of the special collections are so vast that not all of the material they include can be brought up from the stacks at once.
Some of the materials may be taken out from the library, although most may not.