Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Sweden - Zeppelin Flight - 1936 (May 6-9), Airship ''Hindenburg'' 1st NAF cover, franked by three values, tied by Malmo ''4.5.36'' ds, letter ''c'' (Frankfurt) red confirmation cachet, arrived to NYC on May 9, VF, Sieger #406C