60 Kop. on 60 Kop. workers, the extremely rare proof print on marked registered cover "PSKOW 68" has authentic overprint, the Cyrillic postmarks repulses are likewise genuine, the letter is not postal transported become, the stamp is in perfect condition! great rarity of the area, unsigned and photo expertize Walter Zirath BPP: ". defects are indistinguishable. the perforation is for this issue typically. this is a rarely proof print. there are only issued 24 piece. ", Michel 4.000.-