Ouyang Xiu et al. Xin Tangshu "vol. 219", section "Shiwei" quote: "北有大山,山外曰大室韋,瀕於室建河,河出俱倫,迆而東;河南有蒙瓦部,其北落坦部". translation: "In the north there are great mountains, beyond the mountains are the Great Shiwei, they are situated next to the river Shijian; the river flows from [lake] Julun, windingly eastwards; south of the river are the Mengwa tribe, north of them were the Luotan tribe."
Jiu Tangshu, "vol. 199b", section Shiwei quote: "其北大山之北有大室韋部落,其部落傍望建河居。其河源出突厥東北界俱輪泊,屈曲東流,經西室韋界,又東經大室韋界,又東經蒙兀室韋之北,落俎室韋之南". Translation: "In the north, there are great mountains, north of which there is the Great Shiwei tribe; that tribe dwells next to the Wangjian river. That river's originates from Lake Julun north-east of the Tujue's boundary, flowing windingly eastwards; it borders the West Shiwei, further east it borders the Great Shiwei, further east it flows north of the Mengwu Shiwei [and] south of the Luozu Shiwei."