Kutadgu Bilig
The Kutadgu Bilig or Qutadğu Bilig (; Khaqani Turkic: [qʊtɑðˈɢʊ bɪˈlɪɡ]) is an 11th-century work written by Yūsuf Khass Hajib for the prince of Kashgar. The text reflects the author's and his society's beliefs, feelings and practices with regard to quite a few topics and depicts interesting facets of various aspects of life in the Kara-Khanid Khanate.