Soviet Union. Michel 383 etc. on cover, 1930 Children's aid 10+2 k olive perf 10½ etc. on air mail cover carried by "FLUGSCHIFF Do.X" Leningrad-Passau-Budapest. Mixed franking with German Reich Mi 479, 480 and 482. (479 and 480 in tête-bêche pairs). Scarce item!