Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Germany - Zeppelin Flights - 1933 (June 20), Two Short Flights to Switzerland, cover franked by two stamps, including Zeppelin 1m carmine, tied with on-board ''20.6.33'' cancel, ''Mit Luftschiff ''Graf Zeppelin'' line confirmation marking, VF and scarce, Sieger #0216 I, C.v. €250 plus €100 as a premium for franking, Scott #C35