《明史·列传·卷四十一》
请在青浦筑一座土山，周长百丈，高三十余丈，在上面建望楼，作为标志。 
请于青浦筑土山，方百丈，高三十余丈，立堠表识。 
I request your permission to build an artificial mountain in Qingpu, 100 zhang in circumference and over 30 zhang high, and a watchtower on top as a landmark. 