In calligraphy inscriptions, "book" has a specific meaning. Generally speaking, calligraphy is divided into two aspects: content and form. The content can be a poem or an idiom, which is not created by the calligrapher himself. Form refers to the characters in a work and their related calligraphy elements. Therefore, signatures generally need a "book", which means that the previous name is limited to "calligrapher" rather than "writer".
If you are both a writer and a calligrapher, you will generally use "title".
Therefore, as long as the format is sufficient, it still falls on the "book (topic)".
There is one exception: the format is not enough. At this time, I can only write poor money, and I don't write anything except my name and seal.