European power exchanges:

Nord Pool Spot (Scandinavian and Baltic countries)
EPEX (France, Germany, Switzerland, Austria)
GME (Italy)
OPCOM (Romania)
HEnEx (Greece)
POLPX (Poland)
OMIE (Spain and Portugal)
EPEX, former APX (Netherlands)
EPEX, former BELPEX (Belgium)
OKTE (Slovakia)
OTE (Czech Republic)
HUPX (Hungary)
SOUTHPOOL (Slovenia)
EXAA (Austria)
EPIAS (Turkey)
CROPEX (Croatia)
SEEPEX (Serbia)
 
Bulgarian Institutions and organizations:

Ministry of Energy
Energy and Water Regulatory Commission
Bulgarian Energy Holding EAD
Electricity System Operator EAD
 
European Institutions and organizations:

EUROPEX
APEX
ACER
ENTSO-E
EUROELECTRIC
International Energy Agency
Energy Community