《宋书·志·卷二十七》
《易运期》说： 言居束，西有午，两曰并光曰居下，原为君主，反而成为辅佐，五八四十，黄气承受，真人出现。 
《易运期》曰： 言居东，西有午，两日并光日居下。其为主，反为辅，五八四十，黄气受，真人出。 
The book Yiyun Qi says: the word “speak/talk/say” is contained within the character Dong, and sunset is located in west. When the character sun and character moon appear at the same time, it means staying at the lower position, which originally belonged to the monarch, but instead became his assistant. Five eight forty, the yellow gas endures, the true person arrives.