ISBN 0-313-31686-4. https://books.google.com/books?id=fWbICgEc2LwC Ward, A.W. and G. P. Gooch, eds. The Cambridge History of British Foreign Policy, 1783-1919 (3 vol
1898-1914, Volume IV, The Anglo-Russian Rapprochement 1903-7. Edited by G.P. Gooch and H Temperley. Her Majesty's Stationary Office, London 1929. p618-621