Grenard, Fernand (1904). Tibet: The Country and its Inhabitants. Fernand Grenard. Translated by A. Teixeira de Mattos. Originally published by Hutchison and Co., London. 1904. Reprint: Cosmo Publications. Delhi. 1974.
Hill, John E. (2009) Through the Jade Gate to Rome: A Study of the Silk Routes during the Later Han Dynasty, 1st to 2nd Centuries CE. John E. Hill. BookSurge, Charleston, South Carolina. ISBN978-1-4392-2134-1.
Millward, James A. (2007). Eurasian Crossroads: A History of Xinjiang. Columbia University Press, New York. ISBN978-0-231-13924-3.
Roerich, George N. (1931). Trails to Inmost Asia: Five Years of Exploration with the Roerich Central Asian Expedition, pp. 49–51. First reprint in India. Book Faith India, Delhi. (1996). ISBN81-7303-032-4.
Shaw, Robert. (1871). Visits to High Tartary, Yarkand and Kashgar. Reprint by Oxford University Press (1984). ISBN0-19-583830-0.
Younghusband, Francis E. (1896). The Heart of a Continent. John Murray, London. Facsimile reprint: (2005) Elbiron Classics.