1977 PLATE PROOF COB51, Exhibition Socfilex in Berlin, comp. 4 pcs of plate proofs, 3x printed stmp 6Kčs, from that 1x master die in/at definitive colors, 2x in/at brown and black color, 1x plate proof added-print on envelope, supplemented with standard envelope, all on carton paper with wide margin; good condition 1984 NÁVRH / maketa on/for nepřijatou p.stat envelope A. Zápotocký 1884 - 1984, with usage gravure stamp. Pof.811 also text from miniature sheet Pof.A813 in black color on/for added-print envelope/-s and in brown color on stmp with value 0Kčs, with name Milan Němec + 2 print special postmark 100. anniv of birth A. Zápotockého TURNOV 19.12.1984; production fold in envelope, without fold, rare! 1968 PLATE PROOF printed stmp Prague 60h from postal stationery covers COB23, in/at grey-blue color on/for carton paper with wide margin - MS arrangement, signature of engraver J. Herčík; very fine 1975 PLATE PROOF COB44, Exhibition Socfilex in Moscow, comp. 4 pcs of plate proofs, 3x printed stmp 6Kčs, from that 1x master die in/at definitive colors, 2x in/at grey-violet and black color, 1x plate proof added-print on envelope, supplemented with standard envelope, all on carton paper with wide margin; good condition