Commercial air mail cover from MITYLENE to STOCHOLM (SWEDEN). Postmarked with ‘MYTΙΛΗΝΗ * 4 OKT 45’. Censored upon departure with a violet 2-circled bilingual rubber stamp ‘ΕΛΛ ΕΛΕΓΧΟΣ * GREEK CENSOR’ and bilingual also resealing tape (type 1592) texted ‘ΗΝΟΙΧΘΗ ΥΠΟ ΤΟΥ ΕΞΕΤΑΣΤΟΥ 71 / OPENED BY EXAMINER No 71’ after examining contents.
On its way to SWEDEN passed from LONDON (which functioning as first exchange office for the forwarding to the second), where hand stamped with the red rubber air mail marking O.A.T. [Onward Air Transmission].
The place these marking was used is not shown because the reason of their existence was to facilitate the transfer of the mail by supplying information from one postal administration to another, as imposed from U.P.U. for the categories of postal articles.

Note: There are at least 15 types of air mail markings O.A.T.