《宋书·志·卷二十二》
上为《关背德曲》共二十一句，其中八句每句四字，二句每句六字，七句每句五字，四句每句三字。
右《关背德曲》凡二十一句，其八句句四字，二句句六字，七句句五字，四句句三字。
There are 20 sentences in the "Guande Back Virtue Song", including eight sentences with four characters each, two sentences with six characters each, seven sentences with five characters each, and four sentences with three characters each.