《宋书·志·卷三十四》
晋武帝太康九年，幽州塞北有死牛头说话。造近于牛祸。
牛祸：晋武帝太康九年，幽州塞北有死牛头语。近牛祸也。
In the ninth year of Emperor Wu of Jin's Taikang Dynasty, a dead cow's head spoke in the north of the Youzhou Fortress. This is close to the disaster of cattle.