1920 Surtax for ex-Prisoners of War, specialized collection on pages, perf. and imperf. blocks of four, commercially used cover with 10s rose, with 2016 Thomas Hitzler certificate stating that this is one of a maximum 15 recorded non-philatelic covers, strip of three of 5s green, surcharge shifted and practically omitted from the left stamp (Karaivanoff certificate), inverted overprints, large perf. and imperforate multiples, philatelic covers, additional varieties, fine-v.f. (Cat No. B1/10,var) (Image)

Est.US$1,500

1920 (10 Apr) picture postcard franked with 5s on 10s (for the returning POWs), tied by bilingual Gabrovo departure cds and sent to Jambol. The postcard is underfranked (should have been 10s) and according to the accompanying Thomas Hitzler certificate "only a few non-philatelic covers are recorded. It is estimated that a maximum of 15 non-philatelic covers exist. This is a very rare and nice cover, one of a few recorded" (Cat No. B3) (Image)

Est.US$400

1920 (19 Sep) cover (with letter of contents) franked with 7 1/2s on 15s (for the returning POWs), tied by bilingual Kazanlik departure cds and sent to Sofia. The cover is underfranked (should have been 25s) and according to the accompanying Thomas Hitzler certificate "only a few non-philatelic covers are recorded. It is estimated that a maximum of 15 non-philatelic covers exist. This is a very rare and nice cover, one of a few recorded" (Cat No. B4) (Image)

Est.US$400