《汉书·传·外戚传上》
当初，武帝能够被立为太子，长公主出力很多，就娶了长公主的女儿为妃子。
初，武帝得立为太子，长主有力，取主女为妃。
Back then, the Martial Emperor was made Crown Prince largely due to the efforts of the Chang Princess, and so he took the Chang Princess’s daughter as his concubine.