What are the characteristics of Song Cong's calligraphy works?

Song Yan's calligraphy works include the cursive script Jingtie and the regular script Postscript of Du Qiutu. His calligraphy runs from family to family, and he shared weal and woe with Du Huan. Its cursive script is smooth and vigorous, and its regular script is beautiful. At that time, people said that his seal script was the best, but unfortunately he didn't leave any works. However, from his vigorous cursive strokes and rounded turns, we can still see the influence of seal script on him.

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