Memorandum respecting the boundary between Persia and Russia; and the understanding between Great Britain and Russia as to the maintenance of the independence and integrity of Persia. E Hertslet, Foreign Office, 22 Apr 1874
Precis of correspondence between Her Majesty's Embassy and Her Majesty's Foreign Office on question of northern frontiers of Afghanistan and the understanding between Russian and British governments respecting Central Asia 1869-71. Foreign Office, 6 Jan 1872