Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Vatican City - Zeppelin Flight - 1936 (May 6-9), Airship Hindenburg 1st North America Flight mixed franking cover to USA, bearing Catholic Congress 25c green and two Italian air post values, Frankfurt connection ''5.5.36'' date stamp on reverse and red confirmation letter ''c'' cachet, NYC ''May 9.1936'' arrival marking, VF, Si #406, C.v. €700, Est. $400-$500, Scott #43