《资治通鉴·唐纪·唐纪四十一》
河东的军队因在百井遭到惨败，骑兵势单力薄，马燧便征召牧马奴仆，共得数千人，教练数月，都成为精锐骑兵。
河东承百井之败，骑士单弱，燧悉召牧马厮役，得数千人，教之数月，皆为精骑。
Due to the disastrous defeat at Baijing, the Hedong army was weak in cavalry, so Ma Sui recruited herders and servants, totaling thousands of people, who were trained for several months and all became elite cavalry.