Registered cover from "ΚΕΡΚΥΡΑ*25.ΜΑΙ.31" to London, canc. with "IMPERIAL AIRWAYS ENGLAND-INDIA LINE*FIRST AIRMAIL CORFU-LONDON*MAY.1931", with cachets "UNCLAIMED", "RETURN TO WRITER" and air-cachet type 16A in red, returned to "ΑΘΗΝΑΙ*20.ΙΟΥΝ.31", (Hellas 161E).