What does Jiugongge's book look like?

In square grid paper, four lines cross into nine squares. China's traditional calligraphy is to learn to copy the rubbings. Commonly known as tic-tac-toe game. On a square grid paper, four lines cross into nine squares. Jiugongge originated from Ou Yangxun, a calligrapher in the early Tang Dynasty, and was originally designed to transfer and shrink ancient posts.