Bulgaria 1930 (May 13), flown cover from Sofia to Hamburg, franked by ten stamps, delivered by two connected Pioneer Flights Sofia - Nuremberg/Furth and Nuremberg/Furth - Hamburg, two appropriate airpost markings on front, backstamped, punch at right, still F/VF and scarce, Est. $200-$300

150.00

1932 (May 17), Pioneer Flight registered cover Sofia - Paris, franked by air post complete set of three, tied by Sofia "17.V.32" special ds, postmarked on arrival, mostly VF, Est. $100-$150

75.00