Help find works of hard-pen calligraphy and regular script

Regular script is also called Zhengkai, Zhenshu, and Zhengshu. It gradually evolved from the official script and became more simplified, horizontal and vertical. This type of Chinese character font is the traditional handwritten Chinese character that is currently used. "Cihai" explains that it "has a square shape and straight strokes, which can be used as a model." Hence the name regular script. It began in the late Han Dynasty and has been popular ever since. The emergence of regular script closely followed the rules and regulations of the Han Dynasty, and pursued the further development of physical beauty. At the end of the Han Dynasty and the Three Kingdoms period, the writing of Chinese characters gradually changed into waves, stilts, and strokes, and added "side" (dot), " Strokes such as "plunder" (long strokes), "peck" (short strokes), and "ti" (straight hooks) make the structure more rigorous. Such as "Wuwei Medical Slips", "Juyan Han Slips", etc. The characteristic of regular script is that it is neat and orderly. It is a model among fonts, so it is called regular script and has been used to this day.