《资治通鉴·隋纪·隋纪八》
始毕可汗大喜。丙寅，始毕派大臣级失特勒先往李渊的军营，通知他突厥军已经上路。
始毕大喜，丙寅，遣其大臣级失特勒先至渊军，告以兵已上道。
The Tujue leader was very happy. On the first day of the year, he sent officials Shi Tiele to Li Yuan's military camp to inform him that the Tujue army was on its way.