Tham khảo Ngọc_Môn_quan

  1. "Information sign at The Small Fangpan Castle"
  2. Hill (2009), p. 135.
  3. Mallory and Mair (2000), p. 60.
  • Bonavia, Judy (2004). The Silk Road From Xi’an to Kashgar. Revised by Christoph Baumer. 2004. Odyssey Publications.
  • 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. ISBN 978-1-4392-2134-1.
  • Mallory, J.P. and Mair, Victor H. (2000). The Tarim Mummies: Ancient China and the Mystery of the Earliest Peoples from the West. Thames & Hudson. London.