《资治通鉴·唐纪·唐纪五》
如果不迅速进军，窦建德进入武牢，周围各城新归附，必然不能坚守；两敌合力，势力必然强大，怎么会有机可乘呢？
若不速进，贼入武牢，诸城新附，必不能守；两贼并力，其势必强，何弊之承？
If we do not march quickly and Dou Jiande enters Wulao Pass, the surrounding cities which have newly surrendered will definitely not be able to hold out; when the two enemies join forces, their forces will be powerful, how will we find an opportunity?