Kōng shān xiān sheng Yì tú tōng biàn xù 空山先生易圖通變序
Preface to Master Kōngshān’s Yì tú tōng biàn
Anonymous; 1300
The preface to Léi Sīqí’s (KR5d0034) Yì tú tōng biàn 易圖通變, dated 1300. Preserved as DZ 1012 / CT 1012 (Tài xuán bù 太玄部).
Dating. 1300. Dynasty: 元.