Verney L. Cameron, Across Africa, pp. 332-334. London, 1885.

David and Charles Livingstone, Narrative of Expedition to the Zambezi, p. 414. New York, 1866.

Census of the Philippine Islands, Vol. I, pp. 464-466, 565. Washington, 1905.

Stanford's Australasia, Vol. II, pp. 256-257. London, 1894.

A.R. Wallace, The Malay Archipelago, pp. 368, 381. New York, 1869.

Ratzel, History of Mankind, Vol. I, pp. 262-263, 344. London, 1896-1898.

Richard Semon, In the Australian Bush, pp. 340-342, 347. London, 1899.

John L. Stoddard, Lectures, Vol. III, p. 311. Boston, 1903.

John Barrows, Travels in China, pp. 377-379. Philadelphia, 1805.

William M. Wood, Fankwei, pp. 169-174. New York, 1859.