Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Russia and Soviet Union - Zeppelin Flight - 1931 (July 24-31), North Pole Flight card and cover, franked by Zeppelin and Ice-Breaker ''Malygin'' imperforate set of four (30k +1r and 35k and 2r), tied by special date stamps, each one with red flight cachet, Leningrad ''25.VII.31'' or Friedrichshafen ''31.VII.31'' arrival markings, VF, Sieger #120Ab, 120Ba,, Est. $200-$250, Scott #C26-29