Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Incredibly useful reference book

If you're looking to learn the basics of the magazine publishing business, this book is an excellent place to begin. Chapters include (among others): The Magazine as a Storehouse, The Magazine as a Marketplace, Magazine Business Plans, Magazine Production, and Magazines for the Twenty-First Century. Every chapter contains the basic aspects, multiple real-world examples, and a useful list of further reading.