Ottoman Turkey: 1880 (April). Cover to Istanbul franked with 20pa of 1868 with numeral 10 on lower right tablet variety and 1pi of 1876 Dulos stamps for 1 1/2pi single weight up to 100 route-hours letter rate (distance was 87 route-hours) tied by triple box ANKARA 81 (A&P type 3) handstamp and 25 April arrival cds.
