《资治通鉴·梁纪·梁纪六》
北魏任命黄门侍郎杨昱兼侍中，令他持符节监督北海王元颢的军队，去援救幽州，豳州之围因而被解除。
魏以黄门侍郎杨昱兼侍中，持节监北海王颢军，以救豳州，豳州围解。
Northern Wei appointed Yang Yu, a servant in the Yellow Gate, as a guest minister, ordered him to hold a charm to supervise the army of Yuan Hao, the King of the Northern Sea, and go to rescue Youzhou, so the siege of Binzhou was lifted.