《后汉书·列传·郑范陈贾张列传》
八年，下诏诸儒各选高才生学习《左氏》、《谷梁春秋》、《古文尚书》、《毛诗》，从此四经便流行于世。
八年，乃诏诸儒各选高才生，受《左氏》、《穀梁春秋》、《古文尚书》、《毛诗》，由是四经遂行于世。
In the eighth year, an imperial edict was issued ordering all scholars to select highly talented students to study the Zuo Zhuan, Guliang Spring and Autumn, Ancient Text Shangshu, and Mao Poetry. Since then, the four classics have become popular in the world.