1939, 10+10 C. \"Alliance celebration stamps\", variety \"unperforated\", upper margin copy, impeccable mint never hinged, issued only 50 examples - very rare stamp, photo certificates Emil Rellstab International Association for Philatelie Experts and Jean Claude Marchand SBPV (2023) \"in perfect condition. \", Michel 4.500.- (Zumstein no. 2.1.09)