Auction Series 257-264 in Zurich Day 4

1876 (Oct): Envelope from Filibe/Plovdiv to Constantinople bearing Dulos 1875 10 pa. lilac in combination with postage due 1869 2 pi. brown & black-brown perf. 5-11, both tied by clear all-Arabic double circle "FILIBE 81" handstamps in black. Reverse with bilingual STAMBOUL arrival cds (Oct 30, 76). Part of backflap missing, nevertheless an interesting item showing irregular usage of postage due instead of definitive stamps. Cert. Sorani (1995).
Catalogue 257: EUROPE & OVERSEAS