For 2000 years, the Popes have taught consistently on Sacred Music. Here is the book that documents everything, point by point. There are documents here that have been before appeared in English. Papal Legislation Concerning Music is a book that every Catholic musician must own. And Roman Catholic Books is seriously discounting this amazing work – and this publisher is also responsible for rescuing the book from obscurity.
On a person note, this was the book that turned everything around for me. It is absolutely amazing.