http://www.ancient.eu/Silk_Road/
http://www.baike.com/wiki/%E6%B5%B7%E4%B8%8A%E4%B8%9D%E7%BB%B8%E4%B9%8B%E8%B7%AF
https://depts.washington.edu/silkroad/texts/hhshu/hou_han_shu.html
http://www.guoxue.com/shibu/24shi/hansu/hsu_039.htm
http://baike.baidu.com/view/251646.htm
http://pan.baidu.com/share/link?uk=137832388&shareid=1818865857&third=0&adapt=pc&fr=ftw
http://pan.baidu.com/share/link?uk=137832388&shareid=1818865857&third=0&adapt=pc&fr=ftw
http://www.duguoxue.com/ershisishi/5048.html
http://www.duguoxue.com/ershisishi/5048.html
http://www.whyandhow.org/cn/info/218347/index.shtml