Image #1
WORLDWIDE AIR POST STAMPS AND POSTAL HISTORY
Switzerland
Pioneer Flights
Lot #
182 | 
| Scott # C9, C12
| 1930 (December 2), registered cover delivered by Ad Astra Aero Africa Flight on leg Zurich - Cartagena - Alicante, franked by three stamps, blue confirmation cachet, undelivered and returned to Fribourg on December 11, appropriate markings on front and reverse, F/VF . |