10 Pfg dark red-orange vertical pair, 40 Pfg green-olive vertical pair Plebiscite on 20 March 1921 on registered letter to Neisse/Silesia; lower 40 Pfg with only partial overprint, double-circle OPPELN 20 3 21 * * * (apparently unlisted in OS handbook, similar no. 137.2), arrival (20.3.1821) on reverse, good condition, expertised Müller, expertised and Dr. Weinberg BPP photo certificate (1990)