![NICARAGUA - 1929 - VARIETY: 50c pale blue 'OFICIAL' overprint issue further overprinted 'Correo Aereo' in blue with variety OVERPRINT DOUBLE, a fine mint copy. (SG O619b) (NIC/25107)](http://latinamericanphilatelics.com/cdn/shop/products/NIC25107_{width}x.jpg?v=1613579884)
50c pale blue 'OFICIAL' overprint issue further overprinted 'Correo Aereo' in blue with variety OVERPRINT DOUBLE, a fine mint copy. (SG O619b)
50c pale blue 'OFICIAL' overprint issue further overprinted 'Correo Aereo' in blue with variety OVERPRINT DOUBLE, a fine mint copy. (SG O619b)