1913 Hellenic Administration, complete set of 12 values with either red or blue overprint, noted the 20L on 3c and the 1D on 30c with INVERTED OVERPRINT, all tied by Greek-type CAVALLA 7/20-VII-13 cds, last day of validity, Vlastos catalogue numbers: 1-5, 6a, 7, 8, 8A, 9, 10a and 11, cert. Vlastos (Image)