Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Russia And Soviet Union - Zeppelin Flights - 1931 (July 27-31), North Pole Return Flight cover from Ice-Breaker ''Malygin'' to Germany, franked by Zeppelin imperf stamps of 35k and 2r, cancelled''18.VII.31'' by special date stamp, German confirmation cachet and all appropriate markings, Friedrichshafen ''31.7.31'' receiver is alongside, VF, Sieger #120Ab, Est.$150-$180, Scott #C27, C29