Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - Costa Rica - Zeppelin Flight - 1935 (May 11-14), 1st North America Airship Hindenburg Return Flight mixed franking cover from San Jose, franked by 1c deep rose and upon arrival to US uprated by two values, violet US confirmation marking and Frankfurt ''14.5.36'' receiver on the back, VF and rare, Sieger #409L, C.v. €1,200, Est. $500-$600, Scott #C24