Niuchuan (410) — the same event in History of the Northern Dynasties and Book of Wei
History of the Northern Dynasties: Changsun Song's army, returning from the great desert, was surrounded by the Rouran at Niuchuan, and Emperor…
What each source says
Changsun Song's army, returning from the great desert, was surrounded by the Rouran at Niuchuan, and Emperor Mingyuan set out on a northern campaign.
蠕蠕追圍之于牛川
Location: 北史 卷1 永興2年
When the army of Zhangsun Song was surrounded by the Rouran at Niuchuan, the emperor went north to campaign, and the Rouran fled.
夏五月，長孫嵩等自大漠還，蠕蠕追圍之於牛川。
Location: 魏書卷3·永興二年