《旧五代史·后唐·庄宗纪三》
这时节令已到冬至，平地大雪五尺深，敌人缺乏粮草，人马死于道路的绵绵不绝，庄宗乘胜追袭到幽州。
会大雪弥旬，平地数尺，人马死者相属，太祖乃归。
By this time, it was the winter solstice. There was five feet of heavy snow on the flat ground. The enemy lacked provisions, and there was an endless stream of people and horses dying on the roads. Zhuangzong took advantage of his victory and pursued them to Youzhou.