BULGARIAN COIN 20 levs 100 years Sofia University, 1988 Proof
KM #173 Year of issue: 1988 Nominal value: 20 levs Weight: 11.2 g Type of metal: Ag 500 Diameter: 30 mm Mintage: 99 900 Edge: Cyrillic inscription "Ðапред, науката е Ñлънце" - Proof