Du Mu (803 ~ 852), a native of Mu Zhi, was born in Wanzhao, Jingzhao. Wenzong Daiwa was admitted to a scholar in two years. He proofread books in Huangzhou, Chizhou and Mujinggangzhou, and became a calligrapher in China during Wu's reign. "Strict and strange", good at writing poems and understanding the art of war, was called "Xiao Du" in the late Tang Dynasty because of his famous poems. Xuanhe Pu Shu thinks that his cursive style is "vigorous and powerful, and the inside and outside of the article are unified". Du Mu is Shen Chuanshi's assistant, and his calligraphy is closely related to Shen Shi. His ink Zhang Shi Juan is in the Palace Museum.
The paper version of Zhang's poems is 28.2 cm long and 1.62 cm wide. At first, Zhang's poem was titled "Tang Dou Hao Hao Shi", and various schools in Yuan and Ming Dynasties also had inscriptions. It is recorded in Xuanhe Pu Shu, Coral Outline, Textual Research on Painting and Calligraphy of Shigutang and Preliminary Compilation of Shiqu Room. Later, the number of "full tears, short chapters, a book" was not complete. Dong Qichang said, "Mu Zhi wrote a good poem, which won the favor of people in the Six Dynasties. After seeing Yan Liu, Wen Feiqing and Mu Zhi became famous. " His books are heroic, eloquent and precious.