《资治通鉴·齐纪·齐纪一》
刘缵屡次奉命出使，前往北魏，北魏冯太后于是与他私通。
缵屡奉使至魏，冯太后遂私幸之。
Liu Wo was ordered to serve as an emissary to Northern Wei on several occasions, and so the Empress Dowager Feng of Northern Wei had an affair with him.