Ban Gu
The Inscription of Yanran, composed by Ban Gu and engraved on Mount Yanran to commemorate Dou Xian's victory again the Xiongnu, was recorded in the 5th-century "Book of Later Han". The expression "to carve a stone on Yanran" () entered the Chinese language as a synonym for achieving a decisive victory. In 2016, a researchers team of Mongolian national university expedition rediscovered the inscription in the Inil (Delgerkhangai) Mountains in southern Mongolia". The 220 legible characters of the inscription, out of a total of 260, are identical to the text recorded in the "Book of the Later Han".