GJ.1, 1c. Little Envelope 12¼ with handstamped horizontal overprint, mint full original gum, excellent quality, extremely rare, signed by Victor Kneitschel on back. (Image)

GJ.2a, 1c. Little Envelope, perf 14¼, handstamped INVERTED horizontal overprint, mint original gum, excellent quality, very rare! (Image)

GJ.3, 2c. Vicente López, mint part gum, very fine quality, very rare! (Image)

GJ.4, 4c. Moreno, mint without gum, very fine quality! (Image)

GJ.5, 8c. Rivadavia, used, excellent quality, rare, signed by Victor Kneitschel on back. (Image)

GJ.6, 12c. Little Envelope with handstamped horizontal overprint, VF, rare! (Image)

GJ.6b, 12c. blue Little Envelope, variety "2 WITHOUT SERIF", mint, very fine quality, rare, signed by Kneitschel (Image)

GJ.7b, 2c. Vicente López with handstamped DOUBLE diagonal overprint, used, extremely rare, VF quality! (Image)

GK.9, 60c. Posadas with diagonal overprint, mint original gum, very fine quality, rare! (Image)

GJ.12a, with INVERTED OVERPRINT variety, mint without gum, very fine quality, rare! (Image)

GJ.13c, 1c. Little Envelope, pair with DOUBLE overprint, BOTH INVERTED, mint, very fine quality, very rare! (Image)

GJ.15b, 4c. Moreno with variety "O" of OFICIAL incomplete, mint original gum, excellent quality, rare! (Image)

GJ.15, 4c. Moreno with variety VERY SHIFTED OVERPRINT, very fine quality! (Image)

GJ.16b, 8c. Rivadavia, pair, the top stamp with variety "F" of OFICIAL incomplete, mint original gum, very fine quality, very rare. Variety not yet catalogued, it will be included in the next edition of the GJ catalog. (Image)

GJ.16, block of 4 with variety SHIFTED OVERPRINT, mint, VF quality! (Image)

GJ.18, 10c. Belgrano, the overprint shifted toward top-left, mint without gum, VF quality, rare, signed by Kneitschel on back. (Image)

GJ.23, 20c. Vélez Sársfield, mint full original gum, excellent quality, signed by Kneitschel (initials) on back, scarce in this superb quality! (Image)

GJ.26, 25c. Alvear, mint part gum, signed by Kneitschel on back, VF quality! (Image)

GJ.27, 30c. Alvear, mint without gum, VF quality, guarantee mark of Rosauer on back (Image)

GJ.28, 60c. Posadas, mint part gum, signed by Kneitschel on back, VF quality! (Image)

GJ.28a, 60c. Posadas with INVERTED overprint, used, excellent quality, very rare, signed by Victor Kneitschel on back (Image)

GJ.29, 90c. Saavedra, mint original gum, signed by Kneitschel on back, VF quality! (Image)

GJ.31d, 4c. Moreno with red normal overprint ON BACK, without overprint on front, mint original gum, excellent quality and extremely rare. NOTE: The catalog describes this variety as with inverted overprint, which is a mistake, it corresponds to GJ.30c (Image)

GJ.33, 60c. Posadas with red overprint, mint original gum, VF quality! (Image)

GJ.33a, 60c. Posadas, mint block of 4 with full original gum, MNH, very fine quality, extremely rare! (Image)