Auction #93 Worldwide Air Post stamps and postal history, Zeppelin Flight items, philatelic rarities of the World

1933-34, International Airlines, Ltd First Flight cover from Croydon to Plymouth, bearing semi-official 3p black on yellow paper, an unused stamp is included (Sanabria #504); and Highland Airways, Ltd First Flight from Inverness (Scotland) to Orkney Isles, franked by King George V stamp of 1½p orange brown, all with appropriate markings and arrival ds on reverse, VF, Est. $150-$200