Registered cover sent from PUERTO RUIZ (Entre Ríos) to Buenos Aires on 25/OC/1914 franked with 42c. (Plowman stamps with M.M. overprint), fantastic! (Image)

RARE MIXED POSTAGE: Registered cover posted on 31/JA/1939, franked with 45c. combining one 5c. Moreno with 'M.A.' overprint and 4x 10c. Rivadavia with 'SERVICIO OFICIAL' ovpt, VF and rare! (Image)

RARE MIXED POSTAGE: Registered cover posted on 26/OC/1940, franked with 40c. combining one 2c. Urquiza with 'M.R.C.' overprint and 3 values with 'SERVICIO OFICIAL' ovpt, VF and rare! (Image)

RARE MIXED POSTAGE: Registered cover posted on 11/AU/1941, franked with 35c. combining several stamps of 1c. and 2c. with 'M.A.' overprints and pair of 10c. Rivadavia with 'SERVICIO OFICIAL' ovpt, VF and rare! (Image)