2 1/2 piastre on 50 Pf in b-colour with 10 Pf in a-colour on properly franked registered letter from Constantinopel 7 / 6 90 to Oldenburg (arrival postmark 10.6.90), photo expertize Dr. Friedrich F. Steuer VÖB: "genuine, especially fresh colours and in good legitimate condition. " Michel 1.420.-