《南齐书·列传·卷五十七》
截断平城西部为宫城，四角建楼，城墙上面呈凹凸形，门内不设屋，城墙又没有壕沟。
截平城西为宫城，四角起楼，女墙，门不施屋，城又无堑。
The western part of Pingcheng was cut off as the imperial palace, with towers built on the four corners, and the city wall was concave and convex, with no houses inside the gate, and there was no moat outside the city wall.