Who were the four schools in the early Tang Dynasty in the history of calligraphy? And tell their representative works.

In the early Tang Dynasty, the four great poets were Ou Yangxun, Yu Shinan, Xue Ji and Chu Suiliang from China.

Masterpiece:

Ou Yangxun: Inscription of Liquan in Jiuchenggong.

Yu Shinan: Confucius Temple Monument

Learning: A Monument to Believing in Zen Master

Chu Suiliang: Preface to Relieving the Mind (Preface to Yanta Religion)