《晋书·志·第六章》
姑洗之笛，正声应合姑洗律，下征应合应钟律，长二尺二寸三分三厘挂零。
姑洗之笛，正声应姑洗，下徵应应钟，长二尺二寸三分三厘有奇。
The Guxi flute, whose main notes correspond with the Guxi mode, and whose lower notes correspond with the Yingzhong mode, is 68.66 cm long.