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Cyril KIDD, The Irish Mail, 3rd edition. TPO and Seapost Society, 2009. 29pp.
R. KIRK, Australian Mails via Suez 1852-1926. The Postal History Society, 1989. 324pp.
A.D. LOVELOCK, Postal Markings of the Holyhead and Kingstown Packet, 1860-1925. Woking: TPO and Seapost Society, 2002. 119pp.
A. G. RIGO DE RIGHI, 350 Years of Anglo-American postal links. London: National Postal Museum, 1970. 16pp.
Alan W. ROBERTSON, The Maritime Postal History of London (Published on the Occasion of The London International Stamp Exhibition 9th to 16th July 1960). Robson Lowe Ltd, 1960.
— A History of the Ship Letters of the British Isles. Volume 1. Limassol, Cyprus: James Bendon Ltd, 1995.
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Howard ROBINSON, Carrying British Mails Overseas. London: George Allen & Unwin Ltd, 1964. 328pp.
Frank STAFF, The Transatlantic Mail. Toronto: Adlard Coles Ltd in Assoc. with Harrap & De Graf, 1956. 192pp.
Colin TABEART, Robertson Revisited: A study of the Maritime Postal Markings of the British Isles based on the work of Alan W. Robertson. Limassol, Cyprus: James Bendon, 1997. 314pp.