Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Soviet Union - 1932, Airship over the Dnieper Dam, 15k gray black, perforation 14, used on registered philatelic exchange cover from Moscow to Prague together with five other values in 1936, two tax stamps on reverse tied by 13- line cachet, address partly erased, otherwise VF and scarce franking, Scott #C25b