Unpublished typescript memoirs, 1893-1969, including: accounts of life in the British colony in St Petersburg before World War One; work in the British Military Mission at the Russian War Office; events witnessed during the Russian Revolution and conditions for the Russian Army during the Revolution, 1917-1918; evacuation of British personnel from Russia, February 1918; negotiating with Finnish Red and White commanders while travelling through Finland during the Civil War; liaising with Admiral Aleksandr Vasiliyevich Kolchak and the White armies in Harbin, China, 1918; liaising with General Mikhail Konstantinovich Dieterichs, Czechoslovak Legions, and a special mission to Ataman Grigory Mikhaylovich Semyonov (or Semenov) in Chita, Transbaikalia, November 1918; activities as General Sir Harry Knox's liaison officer at the White Army Headquarters in Omsk, November 1918 - November 1919; the retreat from Omsk to Vladivostock following the success of the Bolshevik army, November 1919 - March 1920; stationing in Gibraltar and Egypt, 1921-1922; life and work in Simla, Waziristan and Kamptee, India, 1922-1928; work as an intelligence officer, Meshed, Persia (Iran), 1928-1931; life and work in Bombay, Ajmer, Jhansi, Alwar and Delhi, India, 1932-1935, including description of rioting under the Maharajah of Alwar; experiences working in India, China and Egypt during World War Two, including visit to Palestine; account of working in the post-war timber trade and as a consultant in the Russian Section of the London Chamber of Commerce. Also article 'Anglo-Russian Timber Trade: Personal Reminiscences and Reflections of Col L Steveni', The Timber Trades Journal , 11 March 1961, and article by Richard J Aldrich, University of Nottingham, from Modern Asian Studies 32, 1 (1998), pp. 179-217, entitled "Britain's Secret Intelligence Service in Asia during the Second World War" including analysis of Steveni's role as Director of British Secret Intelligence Service (SIS) in Asia.

Two manuscript narrative diaries by Webb-Bowen, detailing the voyage of HMS IRON DUKE to the Crimea, Russia, via Gibraltar, Malta, Suda Bay, Crete, and Constantinople, Turkey, and subsequent operations in the Black Sea and Turkey, 21 Mar 1919-30 Nov 1920; typescript orders by Adm Sir John Michael de Robeck, 1st Bt, Commander-in-Chief, Mediterranean Fleet, for officers and men of HM Ships IRON DUKE, MARLBOROUGH, BENBOW, MONTROSE, SPEEDY and SPORTIVE, relating to landing operations against Nationalist Turkish forces, Gemlik and Yeni Keui, Turkey, Jul 1920.