《辽史·本纪·卷二》
府中多次请求择任宗室，皇上以旧制不可随意变更；请求不断，便告祭于宗庙而后授之。
府中数请择任宗室，上以旧制不可辄变；请不已，乃告于宗庙而后授之。
The Southern Palace made a request to the King to appoint a member of the Royal Family to the post. However, the King declined it, because it went against the tradition. The Southern Palace kept requesting, and finally the King made a sacrifice at the ancestral temple and then appointed a member of the Royal Family to the post.