Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Reviewing Close Harmony

This is an excellent book. I can not praise it enough. Only the writer knows how many hours of research went into the making of this book. It is not only a book that tells the story of southern gospel music, it is written in such a way that it is the history book of southern gospel shape note music. I doubt that there will ever be another book that will preserve gospel heratage as much as "Close Harmony".