Ratzel, History of Mankind, Vol. III, pp. 253-254. London, 1896-1898.
H.J. Mackinder, The Rhine, pp. 27-31, 47-49, 56, 57. London, 1908.
E.P. Knight, Where Three Empires Meet, pp. 305-306. London, 1897.
B.H. Baden-Powell, The Indian Village Community, pp. 136, 143-146. London, 1896.
D.G. Hogarth, The Nearer East, pp. 229-231, 248, 252-253. London, 1902.
Sir Thomas Holdich, India, pp. 243-244. London, 1905.
Niebuhr, Travels Through Arabia, Vol. II, pp. 50-51. Edinburgh, 1792.
B.H. Baden-Powell, The Indian Village Community, pp. 40, 47, 110, 121, 151-154, 159. London, 1896.
Captain J. Forsythe, The Highlands of Central India, pp. 10-15, 23-24, 123-125. London, 1889.
Ibid., 6, 7, 10-12, 141-147.