Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Danzig - Zeppelin Flights - 1929 (March 25-28), Oriental Flight cover, franked by three air post values, including 2½ g brown, tied by Danzig ''21.3.29'' oval ds, Friedrichshafen ''23.MRZ.2'' connection and red confirmation cachet, Istanbul arrival is on reverse, VF, Sieger #23, C.v. €350++, Scott #C26-27, C29