French army postal service Upper Silesia 10 Pfg red orange, 20 Pfg blue postage stamps issue smelting works and peace pigeon 1920 on picture postcard (s / w) with CTO single circle TRESOR ET POSTES * 2 -5 20 * 184 * (OS handbook number FP2 c), French text at back, picture postcards topic: Gliwice view of the street at the Rossmarkt, good condition