The "STützerbach-Format" (STF) was the DARC's standard format for contest log exchange. When they decided to not accept STF files any longer, they deleted the specification in spring 2016 from their server.
The format has some advantages over the Cabrillo format and is still in use, mostly in Germany. You find a copy of the specification in german language on my homepage. The english version is available on the Internet Archive.
