pls also write down some introduction with screenshot, thanks

Project 1: Project Name: Experiment on DTD Project Description: Given a XML document in part III Please Write down the DTD according to the document and the following requirements 1) The element publisher is required. 2) The count of element author is no more than 5. 3) Add another three features for the element book with attribute or sub-element, which is optional. 4) Add another three features for the element author with attribute or sub-element, which is optional. III. XML Document Content in books.xml Wuhan UniversityCauthor >Zhang San Li Si Qinghua University Zhang San Cauthor>Wang Wu Wuhan University Li Si Cauthor > Wang Wu book year="2018"> Wang Wu Ma Liu Wuhan University Ma Liu Yuan Qi Qinghua UniversityYuan Qi Cauthor>Zhang san