Typographic overprints - 'Postal History - Covers'

Quality: ✉

1910 N° 35L ‘50c. olive’ with ‘CONGO BELGE’ typographical error overprint, locally cancelled with Type 5, and ‘25c. blue’ and ‘1fr. carmine’ with the same overprint typo, registered post sent from Leopoldville on 17 March 1910 to Libreville, tariff and very rare mixed franking, sent by the Leopoldville postmaster, certificate by Luc Vander Marcken, very fine