10 Pfg to 1 Mark postage stamps issue with overprint "Plesbiscite 20 mars 1921. ", in perfect condition mint never hinged, expertized Landre and photo expertize Gruber BPP (2013) : "genuine and in perfect quality. ", Michel 800.- - mint never hinged a scarce Sentence edition! Ex collection Rolf Pingel (130. Dr. Fischer auction), ex collection Nitaha