Historical Map of Sikkim in northeastern India
Historical Map of Sikkim in northeastern India extracted from map prepared by Trelawney Saunders, 1876, titled "The routes of Bogle, Turner and Manning between Bengal and Tibet" and published in the book, Narratives of the Mission of George Bogle to Tibet, and of the Journey of Thomas Manning to Lhasa, by Clements R. Markham, C.B., F.R.S. Geographical Department, India Office. Published by London: Trübner and Co., Ludgate Hill. 1876.