Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Switzerland - Zeppelin Flights - 1931 (June 6), Magdeburg Return Flight postcard from Romanshorn to Budapest, franked by two air post values, Magdeburg violet connection marking, red Flight cachet, Friedrichshafen ''7.6.31'' arrival ds, mostly VF, Sieger #109 var, Est. $150-$200, Scott #C10-11