《明史·列传·卷二十二》
念及辽阳是重地，又设立都指挥使司统辖诸卫，任命叶旺、马云为都指挥使，前去镇守。
既念辽阳重地，复设都指挥使司统辖诸卫，以旺及云并为都指挥使往镇之。
Considering that Liaoyang is an important place, the Commander's Office was established to command the guards. Ye Wang and Ma Yun were appointed as Commanders to guard it.