A written work or book — a piece of writing such as a book or scholarly work.
彼の著書は世界中で翻訳されている。
His books have been translated around the world.
大学教授の著書を研究の参考にした。
I used the professor's writings as references for my research.
その著書は近代史について詳しい。
That book is detailed about modern history.