《新唐书·列传·卷一百四十》
当初，东突厥木杆可汗死，不立儿子大逻便，而立弟弟为佗钵可汗。
初，东突厥木杆可汗死，舍其子大逻便，而立弟佗钵可汗。
Originally, when the Eastern Turks' Mugan Khan died, he did not establish his son Dalobi as the khan and instead established his younger brother as Tuoba Khan.