Yan Gang was an officer of Gongsun Zan. In 191 Yan Gang was named Inspector of Ji Province by Gongsun Zan. When Gongsun Zan's younger cousin Gongsun Yue 公孫越 died during the Battle of Yangcheng, Gongsun Zan blamed Yuan Shao for his death and led troops against him. which resulted in a battle near Jie Bridge
- ↑ HHS 73/63, 2359-60 (5b-7b), the Biography of Gongsun Zan.
- ↑ HHS 74/64A, 2380 (6a-b), the Biography of Yuan Shao.
- de Crespigny, Rafe. A Biographical Dictionary of Later Han to the Three Kingdoms. Leiden: BRILL, 2007
- Fan Ye 范曄 (396-446). Hou Han shu 後漢書 "History of the Later Han".