《新唐书·列传·卷一百四十一》
清沔暗暗进军大象龛，半夜，约好城中点火把照得如同白昼，虏兵大惊，清沔袭击虏营后离去。
清沔潜兵大象龛，夜半，约城中举火烛天，虏众惊，因袭其营，乃去。
Qingmian secretly advanced into Daxiangkeng. In the middle of the night, he agreed with the city to light torches to light up the city like daylight. The enemy soldiers were shocked, and Qingmian attacked the enemy camp and then left.