Whose poem and sword dance is Zhang Xu's cursive "Three Wonders"?

Zhang Xu's personality, behavior and calligraphy style were all famous at that time. In Tang Wenzong, the emperor wrote a letter and called it "Three Musts" with Li Bai's poems, Feynman's sword dance and Zhang Xu's cursive script. Zhang Xu once met Feynman and the great painter Wu Daozi in Luoyang. So the three masters gave their unique skills on the spot. Peiman's sword dance is a song, Zhang Xu's cursive script is a wall, and Wu Daozi's painting is a wall. People around him say that they witnessed three wonders in one day, which is a much-told story.