Lingfei Jing's brushwork and its characteristics (pen is a famous post in the past dynasties), by Xu Xiaojun, brand: Xiling Press, version: 1st edition, Xiling Press
This book contains an introduction to the brushwork of the pen and a very detailed explanation. You can practice the basic strokes first, and then practice the shelf structure, but the deficiency of this book is that it is not complete. Books are cheap, not expensive.