《明史·志·卷六十五》
明成祖向北迁都后，完全遵照明太祖时的制度，然而宦官监军，危险的征兆开始出现。
文皇北迁，一遵太祖之制，然内臣观兵，履霜伊始。
After Ming Chengzu moved the capital to the north, he completely followed the system of Ming Taizu. However, the eunuchs supervised the army, and the dangerous signs began to appear.