10c red 'Rivadavia' postal stationery envelope with 'CORREOS Y TELEGRAFOS SERVICIO OFICIAL SIN VALOR POSTAL' overprint in blue sent registered with manuscript 'R 312899' marking and light ESTAFETA FERROVIARIA 32 cds. Addressed to BUENOS AIRES.
10c red 'Rivadavia' postal stationery envelope with 'CORREOS Y TELEGRAFOS SERVICIO OFICIAL SIN VALOR POSTAL' overprint in blue sent registered with manuscript 'R 312899' marking and light ESTAFETA FERROVIARIA 32 cds. Addressed to BUENOS AIRES.