John Brooks, The Battle of Jutland (Cambridge, Cambridge Military Histories, 2016)
Jack Broome, Make a Signal (London, Putnam, 1956) and Make another Signal (London, Harper Collins, 1973)
Charles H Brown, Nicholl’s Seamanship and Nautical Knowledge (Glasgow, Brown Son and Ferguson, 18th Edition 1938 reprinted 1949)
Russell W Burns, Communications: An International history of the formative years (London, Institute of Electrical Engineers, 2004)
Jonathan Clements, Admiral Tojo: Nelson of the East (London. Haus Publishing, 2010)
P Colomb and F Bolton, Flashing Signals Adopted in the Navy and Army (London, Mitchell and Co., 1869)
Sir Julian Corbett, Fighting Instructions 1530-1816 (Project Guttenberg, 2005: Publications of The Navy Records Society Vol. XXIX, 1895)
Martha J Coston, A Signal Success: The Life and Travels of Mrs Martha J. Coston (Philadelphia, Lippincott, 1886)
Tony Ditcham, Life on the Rolling Main, (Barnsley, Seaforth Publishing, 2013)
William Enfield, An Essay Towards the History of Liverpool (London, Joseph Johnson, 1774)
Andrew Gordon, The Rules of the Game, Jutland and British Naval Command (London, Penguin Books, 2015)
R Harding, Seapower and Naval Warfare (London, UCL Press, 1999)
Richard Hough, Admirals in Collision (London, White Lion Publishers, 1959)
–– The Great War at Sea (Oxford, Oxford University Press, 1983)
David Howarth, Trafalgar, The Nelson Touch (London, World Books, 1970)
Dixon Kemp, A Manual of Yacht and Boat Sailing (London, The Field Offices, 1878)
Captain Barrie Kent, RN, Signal! A History of Signalling in the Royal Navy (Petersfield, Hyden House, 1993)
John Millan Signals for the Royal Navy and Ships under Convoy (London, J.Millan, 1746)
W G Perrin, British Flags: Their Early History and Development at Sea (Cambridge University Press, 1922)
Rebecca Raines, Getting the Message Through (Washington, US Army Center for Military History, 1995)
Henry J Rogers, Telegraph Directory and Seaman’s Signal Book (Baltimore, F. Lucas Jr., 1845)
Nigel Steel and Peter Hart, Jutland 1916, Death in Grey Wastes (London, Cassell, 2003)
Christopher H Sterling (ed), Military Communications from Ancient Times to the 21st Century (Santa Barbara, ABC-CLIO, 2008)
W K Stewart, Brown’s Signalling: How to Learn the International Code of Visual and Sound Signals (Glasgow, Brown Son and Ferguson, 1961)
Ben Wilson, Empire of the Deep, The Rise and Fall of the British Navy (London, Weidenfeld and Nicholson, 2013)
Timothy Wilson, Flags at Sea (NMM/Chatham Publishing, 1986)
Timothy S Wolters, Information at Sea: Shipboard Command and Control in the US Navy from Mobile Bay to Okinawa (Baltimore, John Hopkins University Press, 2013)
UK charity working to promote interest in all aspects of flags and flag flying.
UK flag maker. Catalogue includes all Naval and International Code flags.
A good source for everything connected with flags used at sea in the United States.
US flag maker and retailer. Links to sponsored site Flags of the World (FOTW) a resource and forum for serious vexillologists.
Royal Navy Communications Branch Museum and Library.
Private site tracing history of telegraph companies in the UK.
National Museum of the Royal Navy has a comprehensive on-line resource on all aspects of the naval history including flags and signalling.
An extensive archive on all methods of signalling in use during the American Civil War including Martha Coston’s Telegraphic Night Signals. For more on Martha Coston see C Kay Larson, ‘A Woman with Flare’, New York Times, 2.11.2012