1871 letter sent from Havana to Buenos Aires (Argentina), with USA Sc.150, 10C brown and stamp of Great Britain Victoria 4P orange, Sc.43, oval pmk "C83", round ST. THOMAS 29/1871; stamp 4P minor fault, overall very fine, certificate The Philatelic Foundation New York, extremely rare mixed franking of stamps of Great Britain and USA!Starting price: 150 000 CZK