- Schläfli symbol (Wikipedia)
In geometry, the Schläfli symbol is a notation of the form {p,q,r,…} that defines regular polytopes and tessellations.
- Freiberg (Wikipedia)
Freiberg is a university and former mining town in Saxony, Germany. It is a Große Kreisstadt (large county town) and the administrative centre of Mittelsachsen district.