Postage stamp print method change: the same postage stamps issued chronologic with the same print in different printing methods
Edition 1905: engravingEdition 1920: offset printing
Edition 1926: engravingEdition 1930: photogravure
Edition 1982: typographyEdition 1987: letterset printing
Edition 1982: stamp impression in typography
Edition 1984: stamp impression in letterset printing