DAMAS – CAIFFA 1 (RP 11) 15 3 16 vf pmk on 20pa imptd stp paid answer part of a letter card sent to Berlin, Latest Known Date, message in German dated "Jerusalem 13.3.16" & couriered to Haifa, Damas transit, Beirut & Austrian censor marks + UBERPRUFT (examined) all on face; f - vf & Very Rare, ex Schaeffer, certif Tsachor - Aloni
Catalogues:
The Ottoman Posts & Telegraph Offices in Palestine & Sinai – N.J. Collins & Steichele (listed St. PM or PM)
Steichele – "Ottoman Post" (listed w/double Numbers)
Steichele – "Handbook of Holy Land Philately" Vols. I + II – revised by N.J. Collins & L. Dickstein
The Postal History of the Ottoman Post in The Holy Land – Aloni & Hackmey