《南史·本纪·卷一》
十月，张纲制成了攻城器具，设计了飞楼悬梯、木幔板屋，上面盖上牛皮，弓箭就无法奏效了。
十月，张纲修攻具成，设飞楼县梯，木幔板屋，冠以牛皮，弓矢无所用之。
In the tenth month, Zhang Gang manufactured siege machines, designing flying towers and siege ladders, and creating wooden huts covered with cowhide, which made arrows ineffective.