Sutra Name: Taishang Laojun Zhong Sutra. Also known as "Pearl Palace Jade Calendar". Author unknown. Make an appointment with Pu Wei and Jin. It is said that Laozi passed down the first and second chapters of the Tao Te Ching, and this sutra is the middle chapter. Originally one volume, it was divided into two volumes. Original source: Taiqing Department of "Orthodox Taoist Canon". Reference version: "Yun Ji Qi Arc Fat Diao"
