SUDAN 1902 1m brown and pink Official, error, SGO3cSudan 1902 1m brown and pink Official, type O1 overprint, ERROR OVERPRINT INVERTED, SGO3c. A fine mint example with original gum. Trivial gum wrinkles, mentioned for accuracy, but of very fine appearance. A rare error as only six panes of 30 originally existed. Accompanied with a clear British Philatelic Association certificate of authenticity (1975). The Camel Postman stamps of Sudan are considered by the famous printers De La Rue as the most