1918, Polish Corps, 18 values from the two overprinted issues, one 50 k. with inverted overprint, each neatly tied by cds. “POCZTA POLOWA 21 5 18 I POL.KOPR.2” to a large official postal document with negative seals and five-line handstamp “POCZTA Polowa Igo Polskiego Korpusa” alongside, folded several times mostly between the adhesives, still mostly very fine, an impressive document
