Description: STT VUJA. Esperanto Congress. Sheetlet of eight stamps with overprint error ‘Double Marginal Inscription'. Lightly hinged in positions 02 and 07. Sassone Fol. 4a, € 55000.00. This is one of four known miniature sheets with this error. Two are held in major collections and the whereabouts of the third are not known and is possibly lost or split. Therefore this is the only example available for the foreseeable future. An exceptional rarity and the summit of every Trieste B collection.