unused --, 20c. black on chamois with good margins, without gum. Fine and a scarce printing. Robineau certificate (1992). C. 3c; FF 5,000. Photo

Details
unused --, 20c. black on chamois with good margins, without gum. Fine and a scarce printing. Robineau certificate (1992). C. 3c; FF 5,000. Photo