75th Anniversary Universal Postal Union Block of Stamps

FIRST DAY MAIL of is LETTERS Art Craft 10TH ANNIVERSARY ISSUE NEITHER SNOW, NOR RAIN, NOR HEAT, NOR GLOOM OF NIGHT STAYS THESE COURIERS FROM THE SWIFT COMPLETION OF THEIR APPOINTED ROUNDS 75th ANNIVERSARY UNIVERSAL POSTAL UNION CHICAGO OCT 7 9-AM 1949 ILL U.S.POSTAGE AIR MAIL 15 15 24 1874 TRST DAY THE UNIVERSAL POSTAL UNION AMERICAN AIR U.S.POSTAGE AIR MAIL 15 1874 1949 THE UNIVERSAL POSTAL UNION U.S.POSTAGE AIR MAIL 15 15 OFOS SUE 1949 THE UNIVERSAL POSTAL UNION MAIL SOCIETY U.S.POSTAGE AIR MAIL 15 15 1874 1949 THE UNIVERSAL POSTAL UNION