Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Russia And Soviet Union - First and Pioneer Flights - 1928 (September 17-18), First Dobroliot Flight pre-printed registered cover from Moscow to Irkutsk, franked by three adhesives, Dobroliot confirmation cachet and Irkutsk arrival ds, F/VF, Est. $400-$500