Polar travel 1931, Russian post, handing in for transport Leningrad, registered cover with 35 Kop. and 2 R. Zeppelin stamp, latter with left margin of sheet, with PARAVION "ZEPPELIN" Leningrad 25 VII 31 to Kellomäki / Finland with arrival postmark and appropriate Cachet, arrival postmark Malyguin 27 VII, in perfect condition