1912 (September 25), Demonstration Flight over Stockholm postcard, franked by King Gustaf V 5Ö green and bearing Barnens Dag Sverige Forsta Flygpost semi-official air post stamp (50Ö) violet (minor facial abrasion), violet confirmation cachet, Lidingo Villas (Suburb of Stockholm) date stamp, mostly VF, Est. $250- $300 (Image)

1929 (9 June), Trans-Atlantic Pioneer Flight Stockholm - New York, interrupted near Iceland due to technical difficulties, illustrated registered cover franked by 45Ö brown with additional King Gustaf V 5kr in block of four, special confirmation cachet in blue, NYC transit on September 11 and Martinez, CA ''Sep.16.1929'' arrival ds, mostly VF and very scarce, only 65 items were carried, Est. $300-$400 (Image)