《新唐书·列传·卷一百四十八》
宦官们越发恐惧，更加想知道胤的计谋。于是找到识字的美女宗柔等人，安排在皇帝左右，侦察他们的计划。
中官益恐，滋欲得其谋，乃求知书美人宗柔等内左右以刺阴事。
The eunuchs became more and more fearful, and they wanted to know what Yin was planning. So they found literate beauties such as Zong Rou and arranged them around the emperor to spy on their plans.