《新唐书·列传·卷一百四十》
后来西部终于自立欲谷设为乙毗咄陆可汗，与利失交战，死伤不可计数。于是就以伊列河为界，河以西属咄陆，河以东则听命利失。
后西部卒自立欲谷设为乙毘咄陆可汗，而与咥利失交战，杀伤不可计，乃因伊列河约诸部：河以西受令于咄陆，其东咥利失主之。
Later, the west finally established Yugu as Yipi Dulu Khan, and fought with Lishi, with countless dead and injured. So they took the Ili River as the boundary, with west of the river belonging to Dulu and east of the river obeying Lishi.